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* powerpc/kernel: Print actual address of regs when oopsingMichael Ellerman2017-12-191-1/+1
| | | | | | | | | | | | | | | | When we oops or otherwise call show_regs() we print the address of the regs structure. Being able to see the address is fairly useful, firstly to verify that the regs pointer is not completely bogus, and secondly it allows you to dump the regs and surrounding memory with a debugger if you have one. In the normal case the regs will be located somewhere on the stack, so printing their location discloses no further information than printing the stack pointer does already. So switch to %px and print the actual address, not the hashed value. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s: Initialize ISAv3 MMU registers before setting partition tableNicholas Piggin2017-12-061-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | kexec can leave MMU registers set when booting into a new kernel, the PIDR (Process Identification Register) in particular. The boot sequence does not zero PIDR, so it only gets set when CPUs first switch to a userspace processes (until then it's running a kernel thread with effective PID = 0). This leaves a window where a process table entry and page tables are set up due to user processes running on other CPUs, that happen to match with a stale PID. The CPU with that PID may cause speculative accesses that address quadrant 0 (aka userspace addresses), which will result in cached translations and PWC (Page Walk Cache) for that process, on a CPU which is not in the mm_cpumask and so they will not be invalidated properly. The most common result is the kernel hanging in infinite page fault loops soon after kexec (usually in schedule_tail, which is usually the first non-speculative quadrant 0 access to a new PID) due to a stale PWC. However being a stale translation error, it could result in anything up to security and data corruption problems. Fix this by zeroing out PIDR at boot and kexec. Fixes: 7e381c0ff618 ("powerpc/mm/radix: Add mmu context handling callback for radix") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Revert "powerpc: Do not call ppc_md.panic in fadump panic notifier"David Gibson2017-12-052-22/+27
| | | | | | | | | | | | | | | | | | | | | | This reverts commit a3b2cb30f252b21a6f962e0dd107c8b897ca65e4. That commit tried to fix problems with panic on powerpc in certain circumstances, where some output from the generic panic code was being dropped. Unfortunately, it breaks things worse in other circumstances. In particular when running a PAPR guest, it will now attempt to reboot instead of informing the hypervisor (KVM or PowerVM) that the guest has crashed. The crash notification is important to some virtualization management layers. Revert it for now until we can come up with a better solution. Fixes: a3b2cb30f252 ("powerpc: Do not call ppc_md.panic in fadump panic notifier") Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [mpe: Tweak change log a bit] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge tag 'powerpc-4.15-3' of ↵Linus Torvalds2017-12-012-3/+11
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "Two fixes for nasty kexec/kdump crashes in certain configurations. A couple of minor fixes for the new TIDR code. A fix for an oops in a CXL error handling path. Thanks to: Andrew Donnellan, Christophe Lombard, David Gibson, Mahesh Salgaonkar, Vaibhav Jain" * tag 'powerpc-4.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc: Do not assign thread.tidr if already assigned powerpc: Avoid signed to unsigned conversion in set_thread_tidr() powerpc/kexec: Fix kexec/kdump in P9 guest kernels powerpc/powernv: Fix kexec crashes caused by tlbie tracing cxl: Check if vphb exists before iterating over AFU devices
| * powerpc: Do not assign thread.tidr if already assignedVaibhav Jain2017-11-291-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If set_thread_tidr() is called twice for same task_struct then it will allocate a new tidr value to it leaving the previous value still dangling in the vas_thread_ida table. To fix this the patch changes set_thread_tidr() to check if a tidr value is already assigned to the task_struct and if yes then returns zero. Fixes: ec233ede4c86("powerpc: Add support for setting SPRN_TIDR") Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> [mpe: Modify to return 0 in the success case, not the TID value] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc: Avoid signed to unsigned conversion in set_thread_tidr()Vaibhav Jain2017-11-291-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is an unsafe signed to unsigned conversion in set_thread_tidr() that may cause an error value to be assigned to SPRN_TIDR register and used as thread-id. The issue happens as assign_thread_tidr() returns an int and thread.tidr is an unsigned-long. So a negative error code returned from assign_thread_tidr() will fail the error check and gets assigned as tidr as a large positive value. To fix this the patch assigns the return value of assign_thread_tidr() to a temporary int and assigns it to thread.tidr iff its '> 0'. The patch shouldn't impact the calling convention of set_thread_tidr() i.e all -ve return-values are error codes and a return value of '0' indicates success. Fixes: ec233ede4c86("powerpc: Add support for setting SPRN_TIDR") Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Christophe Lombard clombard@linux.vnet.ibm.com Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/kexec: Fix kexec/kdump in P9 guest kernelsMichael Ellerman2017-11-241-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The code that cleans up the IAMR/AMOR before kexec'ing failed to remember that when we're running as a guest AMOR is not writable, it's hypervisor privileged. They symptom is that the kexec stops before entering purgatory and nothing else is seen on the console. If you examine the state of the system all threads will be in the 0x700 program check handler. Fix it by making the write to AMOR dependent on HV mode. Fixes: 1e2a516e89fc ("powerpc/kexec: Fix radix to hash kexec due to IAMR/AMOR") Cc: stable@vger.kernel.org # v4.10+ Reported-by: Yilin Zhang <yilzhang@redhat.com> Debugged-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Tested-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2017-11-251-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: - The final conversion of timer wheel timers to timer_setup(). A few manual conversions and a large coccinelle assisted sweep and the removal of the old initialization mechanisms and the related code. - Remove the now unused VSYSCALL update code - Fix permissions of /proc/timer_list. I still need to get rid of that file completely - Rename a misnomed clocksource function and remove a stale declaration * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) m68k/macboing: Fix missed timer callback assignment treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts timer: Remove redundant __setup_timer*() macros timer: Pass function down to initialization routines timer: Remove unused data arguments from macros timer: Switch callback prototype to take struct timer_list * argument timer: Pass timer_list pointer to callbacks unconditionally Coccinelle: Remove setup_timer.cocci timer: Remove setup_*timer() interface timer: Remove init_timer() interface treewide: setup_timer() -> timer_setup() (2 field) treewide: setup_timer() -> timer_setup() treewide: init_timer() -> setup_timer() treewide: Switch DEFINE_TIMER callbacks to struct timer_list * s390: cmm: Convert timers to use timer_setup() lightnvm: Convert timers to use timer_setup() drivers/net: cris: Convert timers to use timer_setup() drm/vc4: Convert timers to use timer_setup() block/laptop_mode: Convert timers to use timer_setup() net/atm/mpc: Avoid open-coded assignment of timer callback function ...
| * | treewide: setup_timer() -> timer_setup()Kees Cook2017-11-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This converts all remaining cases of the old setup_timer() API into using timer_setup(), where the callback argument is the structure already holding the struct timer_list. These should have no behavioral changes, since they just change which pointer is passed into the callback with the same available pointers after conversion. It handles the following examples, in addition to some other variations. Casting from unsigned long: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... setup_timer(&ptr->my_timer, my_callback, ptr); and forced object casts: void my_callback(struct something *ptr) { ... } ... setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr); become: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... timer_setup(&ptr->my_timer, my_callback, 0); Direct function assignments: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... ptr->my_timer.function = my_callback; have a temporary cast added, along with converting the args: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback; And finally, callbacks without a data assignment: void my_callback(unsigned long data) { ... } ... setup_timer(&ptr->my_timer, my_callback, 0); have their argument renamed to verify they're unused during conversion: void my_callback(struct timer_list *unused) { ... } ... timer_setup(&ptr->my_timer, my_callback, 0); The conversion is done with the following Coccinelle script: spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/timer_setup.cocci @fix_address_of@ expression e; @@ setup_timer( -&(e) +&e , ...) // Update any raw setup_timer() usages that have a NULL callback, but // would otherwise match change_timer_function_usage, since the latter // will update all function assignments done in the face of a NULL // function initialization in setup_timer(). @change_timer_function_usage_NULL@ expression _E; identifier _timer; type _cast_data; @@ ( -setup_timer(&_E->_timer, NULL, _E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E->_timer, NULL, (_cast_data)_E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E._timer, NULL, &_E); +timer_setup(&_E._timer, NULL, 0); | -setup_timer(&_E._timer, NULL, (_cast_data)&_E); +timer_setup(&_E._timer, NULL, 0); ) @change_timer_function_usage@ expression _E; identifier _timer; struct timer_list _stl; identifier _callback; type _cast_func, _cast_data; @@ ( -setup_timer(&_E->_timer, _callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | _E->_timer@_stl.function = _callback; | _E->_timer@_stl.function = &_callback; | _E->_timer@_stl.function = (_cast_func)_callback; | _E->_timer@_stl.function = (_cast_func)&_callback; | _E._timer@_stl.function = _callback; | _E._timer@_stl.function = &_callback; | _E._timer@_stl.function = (_cast_func)_callback; | _E._timer@_stl.function = (_cast_func)&_callback; ) // callback(unsigned long arg) @change_callback_handle_cast depends on change_timer_function_usage@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; identifier _handle; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { ( ... when != _origarg _handletype *_handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg ) } // callback(unsigned long arg) without existing variable @change_callback_handle_cast_no_arg depends on change_timer_function_usage && !change_callback_handle_cast@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { + _handletype *_origarg = from_timer(_origarg, t, _timer); + ... when != _origarg - (_handletype *)_origarg + _origarg ... when != _origarg } // Avoid already converted callbacks. @match_callback_converted depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier t; @@ void _callback(struct timer_list *t) { ... } // callback(struct something *handle) @change_callback_handle_arg depends on change_timer_function_usage && !match_callback_converted && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; @@ void _callback( -_handletype *_handle +struct timer_list *t ) { + _handletype *_handle = from_timer(_handle, t, _timer); ... } // If change_callback_handle_arg ran on an empty function, remove // the added handler. @unchange_callback_handle_arg depends on change_timer_function_usage && change_callback_handle_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; identifier t; @@ void _callback(struct timer_list *t) { - _handletype *_handle = from_timer(_handle, t, _timer); } // We only want to refactor the setup_timer() data argument if we've found // the matching callback. This undoes changes in change_timer_function_usage. @unchange_timer_function_usage depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg && !change_callback_handle_arg@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type change_timer_function_usage._cast_data; @@ ( -timer_setup(&_E->_timer, _callback, 0); +setup_timer(&_E->_timer, _callback, (_cast_data)_E); | -timer_setup(&_E._timer, _callback, 0); +setup_timer(&_E._timer, _callback, (_cast_data)&_E); ) // If we fixed a callback from a .function assignment, fix the // assignment cast now. @change_timer_function_assignment depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_func; typedef TIMER_FUNC_TYPE; @@ ( _E->_timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -&_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)_callback; +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -&_callback; +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; ) // Sometimes timer functions are called directly. Replace matched args. @change_timer_function_calls depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression _E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_data; @@ _callback( ( -(_cast_data)_E +&_E->_timer | -(_cast_data)&_E +&_E._timer | -_E +&_E->_timer ) ) // If a timer has been configured without a data argument, it can be // converted without regard to the callback argument, since it is unused. @match_timer_function_unused_data@ expression _E; identifier _timer; identifier _callback; @@ ( -setup_timer(&_E->_timer, _callback, 0); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0L); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0UL); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0L); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0UL); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_timer, _callback, 0); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0L); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0UL); +timer_setup(&_timer, _callback, 0); | -setup_timer(_timer, _callback, 0); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0L); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0UL); +timer_setup(_timer, _callback, 0); ) @change_callback_unused_data depends on match_timer_function_unused_data@ identifier match_timer_function_unused_data._callback; type _origtype; identifier _origarg; @@ void _callback( -_origtype _origarg +struct timer_list *unused ) { ... when != _origarg } Signed-off-by: Kees Cook <keescook@chromium.org>
* | | Merge tag 'powerpc-4.15-2' of ↵Linus Torvalds2017-11-251-2/+2
|\ \ \ | |/ / |/| / | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "A small batch of fixes, about 50% tagged for stable and the rest for recently merged code. There's one more fix for the >128T handling on hash. Once a process had requested a single mmap above 128T we would then always search above 128T. The correct behaviour is to consider the hint address in isolation for each mmap request. Then a couple of fixes for the IMC PMU, a missing EXPORT_SYMBOL in VAS, a fix for STRICT_KERNEL_RWX on 32-bit, and a fix to correctly identify P9 DD2.1 but in code that is currently not used by default. Thanks to: Aneesh Kumar K.V, Christophe Leroy, Madhavan Srinivasan, Sukadev Bhattiprolu" * tag 'powerpc-4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64s: Fix Power9 DD2.1 logic in DT CPU features powerpc/perf: Fix IMC_MAX_PMU macro powerpc/perf: Fix pmu_count to count only nest imc pmus powerpc: Fix boot on BOOK3S_32 with CONFIG_STRICT_KERNEL_RWX powerpc/perf/imc: Use cpu_to_node() not topology_physical_package_id() powerpc/vas: Export chip_to_vas_id() powerpc/64s/slice: Use addr limit when computing slice mask
| * powerpc/64s: Fix Power9 DD2.1 logic in DT CPU featuresMichael Ellerman2017-11-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | I got the logic wrong in the DT CPU features code when I added the Power9 DD2.1 feature. We should be setting the bit if we detect a DD2.1, not clearing it if we detect a DD2.0. This code isn't actually exercised at the moment so nothing is actually broken. Fixes: 3ffa9d9e2a7c ("powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | Merge branch 'misc.compat' of ↵Linus Torvalds2017-11-171-29/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull compat and uaccess updates from Al Viro: - {get,put}_compat_sigset() series - assorted compat ioctl stuff - more set_fs() elimination - a few more timespec64 conversions - several removals of pointless access_ok() in places where it was followed only by non-__ variants of primitives * 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (24 commits) coredump: call do_unlinkat directly instead of sys_unlink fs: expose do_unlinkat for built-in callers ext4: take handling of EXT4_IOC_GROUP_ADD into a helper, get rid of set_fs() ipmi: get rid of pointless access_ok() pi433: sanitize ioctl cxlflash: get rid of pointless access_ok() mtdchar: get rid of pointless access_ok() r128: switch compat ioctls to drm_ioctl_kernel() selection: get rid of field-by-field copyin VT_RESIZEX: get rid of field-by-field copyin i2c compat ioctls: move to ->compat_ioctl() sched_rr_get_interval(): move compat to native, get rid of set_fs() mips: switch to {get,put}_compat_sigset() sparc: switch to {get,put}_compat_sigset() s390: switch to {get,put}_compat_sigset() ppc: switch to {get,put}_compat_sigset() parisc: switch to {get,put}_compat_sigset() get_compat_sigset() get rid of {get,put}_compat_itimerspec() io_getevents: Use timespec64 to represent timeouts ...
| * | ppc: switch to {get,put}_compat_sigset()Al Viro2017-09-191-29/+2
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | Merge tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2017-11-161-0/+3
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Radim Krčmář: "First batch of KVM changes for 4.15 Common: - Python 3 support in kvm_stat - Accounting of slabs to kmemcg ARM: - Optimized arch timer handling for KVM/ARM - Improvements to the VGIC ITS code and introduction of an ITS reset ioctl - Unification of the 32-bit fault injection logic - More exact external abort matching logic PPC: - Support for running hashed page table (HPT) MMU mode on a host that is using the radix MMU mode; single threaded mode on POWER 9 is added as a pre-requisite - Resolution of merge conflicts with the last second 4.14 HPT fixes - Fixes and cleanups s390: - Some initial preparation patches for exitless interrupts and crypto - New capability for AIS migration - Fixes x86: - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs, and after-reset state - Refined dependencies for VMX features - Fixes for nested SMI injection - A lot of cleanups" * tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (89 commits) KVM: s390: provide a capability for AIS state migration KVM: s390: clear_io_irq() requests are not expected for adapter interrupts KVM: s390: abstract conversion between isc and enum irq_types KVM: s390: vsie: use common code functions for pinning KVM: s390: SIE considerations for AP Queue virtualization KVM: s390: document memory ordering for kvm_s390_vcpu_wakeup KVM: PPC: Book3S HV: Cosmetic post-merge cleanups KVM: arm/arm64: fix the incompatible matching for external abort KVM: arm/arm64: Unify 32bit fault injection KVM: arm/arm64: vgic-its: Implement KVM_DEV_ARM_ITS_CTRL_RESET KVM: arm/arm64: Document KVM_DEV_ARM_ITS_CTRL_RESET KVM: arm/arm64: vgic-its: Free caches when GITS_BASER Valid bit is cleared KVM: arm/arm64: vgic-its: New helper functions to free the caches KVM: arm/arm64: vgic-its: Remove kvm_its_unmap_device arm/arm64: KVM: Load the timer state when enabling the timer KVM: arm/arm64: Rework kvm_timer_should_fire KVM: arm/arm64: Get rid of kvm_timer_flush_hwstate KVM: arm/arm64: Avoid phys timer emulation in vcpu entry/exit KVM: arm/arm64: Move phys_timer_emulate function KVM: arm/arm64: Use kvm_arm_timer_set/get_reg for guest register traps ...
| * | | KVM: PPC: Book3S HV: Run HPT guests on POWER9 radix hostsPaul Mackerras2017-11-011-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes the restriction that a radix host can only run radix guests, allowing us to run HPT (hashed page table) guests as well. This is useful because it provides a way to run old guest kernels that know about POWER8 but not POWER9. Unfortunately, POWER9 currently has a restriction that all threads in a given code must either all be in HPT mode, or all in radix mode. This means that when entering a HPT guest, we have to obtain control of all 4 threads in the core and get them to switch their LPIDR and LPCR registers, even if they are not going to run a guest. On guest exit we also have to get all threads to switch LPIDR and LPCR back to host values. To make this feasible, we require that KVM not be in the "independent threads" mode, and that the CPU cores be in single-threaded mode from the host kernel's perspective (only thread 0 online; threads 1, 2 and 3 offline). That allows us to use the same code as on POWER8 for obtaining control of the secondary threads. To manage the LPCR/LPIDR changes required, we extend the kvm_split_info struct to contain the information needed by the secondary threads. All threads perform a barrier synchronization (where all threads wait for every other thread to reach the synchronization point) on guest entry, both before and after loading LPCR and LPIDR. On guest exit, they all once again perform a barrier synchronization both before and after loading host values into LPCR and LPIDR. Finally, it is also currently necessary to flush the entire TLB every time we enter a HPT guest on a radix host. We do this on thread 0 with a loop of tlbiel instructions. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | | Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-nextPaul Mackerras2017-11-011-24/+11
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This merges in the ppc-kvm topic branch of the powerpc tree to get the commit that reverts the patch "KVM: PPC: Book3S HV: POWER9 does not require secondary thread management". This is needed for subsequent patches which will be applied on this branch. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* | \ \ \ Merge tag 'powerpc-4.15-1' of ↵Linus Torvalds2017-11-1637-398/+1004
|\ \ \ \ \ | | |_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "A bit of a small release, I suspect in part due to me travelling for KS. But my backlog of patches to review is smaller than usual, so I think in part folks just didn't send as much this cycle. Non-highlights: - Five fixes for the >128T address space handling, both to fix bugs in our implementation and to bring the semantics exactly into line with x86. Highlights: - Support for a new OPAL call on bare metal machines which gives us a true NMI (ie. is not masked by MSR[EE]=0) for debugging etc. - Support for Power9 DD2 in the CXL driver. - Improvements to machine check handling so that uncorrectable errors can be reported into the generic memory_failure() machinery. - Some fixes and improvements for VPHN, which is used under PowerVM to notify the Linux partition of topology changes. - Plumbing to enable TM (transactional memory) without suspend on some Power9 processors (PPC_FEATURE2_HTM_NO_SUSPEND). - Support for emulating vector loads form cache-inhibited memory, on some Power9 revisions. - Disable the fast-endian switch "syscall" by default (behind a CONFIG), we believe it has never had any users. - A major rework of the API drivers use when initiating and waiting for long running operations performed by OPAL firmware, and changes to the powernv_flash driver to use the new API. - Several fixes for the handling of FP/VMX/VSX while processes are using transactional memory. - Optimisations of TLB range flushes when using the radix MMU on Power9. - Improvements to the VAS facility used to access coprocessors on Power9, and related improvements to the way the NX crypto driver handles requests. - Implementation of PMEM_API and UACCESS_FLUSHCACHE for 64-bit. Thanks to: Alexey Kardashevskiy, Alistair Popple, Allen Pais, Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Balbir Singh, Benjamin Herrenschmidt, Breno Leitao, Christophe Leroy, Christophe Lombard, Cyril Bur, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo Romero, Haren Myneni, Joel Stanley, Kamalesh Babulal, Kautuk Consul, Markus Elfring, Masami Hiramatsu, Michael Bringmann, Michael Neuling, Michal Suchanek, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud, Sandipan Das, Seth Forshee, Shriya, Stephen Rothwell, Stewart Smith, Sukadev Bhattiprolu, Tyrel Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, and William A. Kennington III" * tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (151 commits) powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature powerpc/64s: Fix masking of SRR1 bits on instruction fault powerpc/64s: mm_context.addr_limit is only used on hash powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundary powerpc/64s/hash: Fix fork() with 512TB process address space powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocation powerpc/64s/hash: Fix 512T hint detection to use >= 128T powerpc: Fix DABR match on hash based systems powerpc/signal: Properly handle return value from uprobe_deny_signal() powerpc/fadump: use kstrtoint to handle sysfs store powerpc/lib: Implement UACCESS_FLUSHCACHE API powerpc/lib: Implement PMEM API powerpc/powernv/npu: Don't explicitly flush nmmu tlb powerpc/powernv/npu: Use flush_all_mm() instead of flush_tlb_mm() powerpc/powernv/idle: Round up latency and residency values powerpc/kprobes: refactor kprobe_lookup_name for safer string operations powerpc/kprobes: Blacklist emulate_update_regs() from kprobes powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace powerpc/kprobes: Disable preemption before invoking probe handler for optprobes ...
| * | | | powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 featureMichael Ellerman2017-11-153-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Recently we added a CPU feature for Power9 DD2.0, to capture the fact that some workarounds are required only on Power9 DD1 and DD2.0 but not DD2.1 or later. Then in commit 9d2f510a66ec ("powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 ERAT workaround on DD2.1") and commit e3646330cf66 "powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 PMU workaround on DD2.1") we changed CPU_FTR_SECTIONs to check for DD1 or DD20, eg: BEGIN_FTR_SECTION PPC_INVALIDATE_ERAT END_FTR_SECTION_IFSET(CPU_FTR_POWER9_DD1 | CPU_FTR_POWER9_DD20) Unfortunately although this reads as "if set DD1 or DD2.0", the or is a bitwise or and actually generates a mask of both bits. The code that does the feature patching then checks that the value of the CPU features masked with that mask are equal to the mask. So the end result is we're checking for DD1 and DD20 being set, which never happens. Yes the API is terrible. Removing the ERAT workaround on DD2.0 results in random SEGVs, the system tends to boot, but things randomly die including sometimes dhclient, udev etc. To fix the problem and hopefully avoid it in future, we remove the DD2.0 CPU feature and instead add a DD2.1 (or later) feature. This allows us to easily express that the workarounds are required if DD2.1 is not set. At some point we will drop the DD1 workarounds entirely and some of this can be cleaned up. Fixes: 9d2f510a66ec ("powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 ERAT workaround on DD2.1") Fixes: e3646330cf66 ("powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 PMU workaround on DD2.1") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/64s: Fix masking of SRR1 bits on instruction faultMichael Ellerman2017-11-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On 64-bit Book3s, when we take an instruction fault the reason for the fault may be reported in SRR1. For data faults the reason is reported in DSISR (Data Storage Instruction Status Register). The reasons reported in each do not necessarily correspond, so we mask the SRR1 bits before copying them to the DSISR, which is then used by the page fault code. Prior to commit b4c001dc44f0 ("powerpc/mm: Use symbolic constants for filtering SRR1 bits on ISIs") we used a hard-coded mask of 0x58200000, which corresponds to: DSISR_NOHPTE 0x40000000 /* no translation found */ DSISR_NOEXEC_OR_G 0x10000000 /* exec of no-exec or guarded */ DSISR_PROTFAULT 0x08000000 /* protection fault */ DSISR_KEYFAULT 0x00200000 /* Storage Key fault */ That commit added a #define for the mask, DSISR_SRR1_MATCH_64S, but incorrectly used a different similarly named DSISR_BAD_FAULT_64S. This had the effect of changing the mask to 0xa43a0000, which omits everything but DSISR_KEYFAULT. Luckily this had no visible effect, because in practice we hardly use the DSISR bits. The lack of DSISR_NOHPTE means a TLB flush optimisation was missed in the native HPTE code, and DSISR_NOEXEC_OR_G and DSISR_PROTFAULT are both only used to trigger rare warnings. So we got lucky, but let's fix it. The new value only has bits between 17 and 30 set, so we can continue to use andis. Fixes: b4c001dc44f0 ("powerpc/mm: Use symbolic constants for filtering SRR1 bits on ISIs") Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/64s: mm_context.addr_limit is only used on hashNicholas Piggin2017-11-133-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Radix keeps no meaningful state in addr_limit, so remove it from radix code and rename to slb_addr_limit to make it clear it applies to hash only. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc: Fix DABR match on hash based systemsBenjamin Herrenschmidt2017-11-132-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 398a719d34a1 ("powerpc/mm: Update bits used to skip hash_page") mistakenly dropped the DSISR_DABRMATCH bit from the mask of bit tested to skip trying to hash a page. As a result, the DABR matches would no longer be detected. This adds it back. We open code it in the 2 places where it matters rather than fold it into DSISR_BAD_FAULT_32S/64S because this isn't technically a bad fault and while we would never hit it with the current code, I prefer if page_fault_is_bad() didn't trigger on these. Fixes: 398a719d34a1 ("powerpc/mm: Update bits used to skip hash_page") Cc: stable@vger.kernel.org # v4.14 Tested-by: Pedro Miraglia Franco de Carvalho <pedromfc@br.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * | | | powerpc/signal: Properly handle return value from uprobe_deny_signal()Naveen N. Rao2017-11-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a uprobe is installed on an instruction that we currently do not emulate, we copy the instruction into a xol buffer and single step that instruction. If that instruction generates a fault, we abort the single stepping before invoking the signal handler. Once the signal handler is done, the uprobe trap is hit again since the instruction is retried and the process repeats. We use uprobe_deny_signal() to detect if the xol instruction triggered a signal. If so, we clear TIF_SIGPENDING and set TIF_UPROBE so that the signal is not handled until after the single stepping is aborted. In this case, uprobe_deny_signal() returns true and get_signal() ends up returning 0. However, in do_signal(), we are not looking at the return value, but depending on ksig.sig for further action, all with an uninitialized ksig that is not touched in this scenario. Fix the same by initializing ksig.sig to 0. Fixes: 129b69df9c90 ("powerpc: Use get_signal() signal_setup_done()") Cc: stable@vger.kernel.org # v3.17+ Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/fadump: use kstrtoint to handle sysfs storeMichal Suchanek2017-11-131-4/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently sysfs store handlers in fadump use if buf[0] == 'char'. This means input "100foo" is interpreted as '1' and "01" as '0'. Change to kstrtoint so leading zeroes and the like is handled in expected way. Signed-off-by: Michal Suchanek <msuchanek@suse.de> Acked-by: Hari Bathini <hbathini@linux.vnet.ibm.com> Signed-off-by: Michal Suchanek <a class="moz-txt-link-rfc2396E" href="mailto:msuchanek@suse.de">&lt;msuchanek@suse.de&gt;</a></pre> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/kprobes: refactor kprobe_lookup_name for safer string operationsNaveen N. Rao2017-11-121-27/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use safer string manipulation functions when dealing with a user-provided string in kprobe_lookup_name(). Reported-by: David Laight <David.Laight@ACULAB.COM> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftraceNaveen N. Rao2017-11-122-18/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Per Documentation/kprobes.txt, we don't necessarily need to disable interrupts before invoking the kprobe handlers. Masami submitted similar changes for x86 via commit a19b2e3d783964 ("kprobes/x86: Remove IRQ disabling from ftrace-based/optimized kprobes"). Do the same for powerpc. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/kprobes: Disable preemption before invoking probe handler for optprobesNaveen N. Rao2017-11-121-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Per Documentation/kprobes.txt, probe handlers need to be invoked with preemption disabled. Update optimized_callback() to do so. Also move get_kprobe_ctlblk() invocation post preemption disable, since it accesses pre-cpu data. This was not an issue so far since optprobes wasn't selected if CONFIG_PREEMPT was enabled. Commit a30b85df7d599f ("kprobes: Use synchronize_rcu_tasks() for optprobe with CONFIG_PREEMPT=y") changes this. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/64s: ppc_save_regs is now needed for all 64s buildsStephen Rothwell2017-11-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 78adf6c214f0 ("powerpc/64s: Implement system reset idle wakeup reason"), added a call to ppc_save_regs() in the book3s code. ppc_save_regs() is only built if XMON and/or KEXEC_CORE are enabled, which is usually the case, however if they're not enabled then the build breaks. Fix it by making the Makefile check also build ppc_save_regs.o if CONFIG_PPC_BOOK3S is enabled. Fixes: 78adf6c214f0 ("powerpc/64s: Implement system reset idle wakeup reason") Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> [mpe: Write change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc: Define set_thread_uses_vas()Sukadev Bhattiprolu2017-11-111-10/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A CP_ABORT instruction is required in processes that have mapped a VAS "paste address" with the intention of using COPY/PASTE instructions. But since CP_ABORT is expensive, we want to restrict it to only processes that use/intend to use COPY/PASTE. Define an interface, set_thread_uses_vas(), that VAS can use to indicate that the current process opened a send window. During context switch, issue CP_ABORT only for processes that have the flag set. Thanks for input from Nick Piggin, Michael Ellerman. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> [mpe: Fix to not use new_thread after _switch() returns] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc: Add support for setting SPRN_TIDRSukadev Bhattiprolu2017-11-111-0/+116
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We need the SPRN_TIDR to be set for use with fast thread-wakeup (core- to-core wakeup) and also with CAPI. Each thread in a process needs to have a unique id within the process. But for now, we assign globally unique thread ids to all threads in the system. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com> Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> [mpe: Simplify tidr clearing on fork() and ctx switch code] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/64: Set DSCR default initially from SPRNicholas Piggin2017-11-103-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Take the DSCR value set by firmware as the dscr_default value, rather than zero. POWER9 recommends DSCR default to a non-zero value. Signed-off-by: From: Nicholas Piggin <npiggin@gmail.com> [mpe: Make record_spr_defaults() __init] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | powerpc/powernv: Avoid waiting for secondary hold spinloop with OPALNicholas Piggin2017-11-102-6/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | OPAL boot does not insert secondaries at 0x60 to wait at the secondary hold spinloop. Instead they are started later, and inserted at generic_secondary_smp_init(), which is after the secondary hold spinloop. Avoid waiting on this spinloop when booting with OPAL firmware. This wait always times out that case. This saves 100ms boot time on powernv, and 10s of seconds of real time when booting on the simulator in SMP. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | Merge branch 'fixes' into nextMichael Ellerman2017-11-106-37/+37
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have some dependencies & conflicts between patches in fixes and things to go in next, both in the radix TLB flush code and the IMC PMU driver. So merge fixes into next.
| * | | | | powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 PMU workaround on DD2.1Nicholas Piggin2017-11-061-12/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DD2.1 does not have to save MMCR0 for all state-loss idle states, only after deep idle states (like other PMU registers). Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 ERAT workaround on DD2.1Nicholas Piggin2017-11-061-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DD2.1 does not have to flush the ERAT after a state-loss idle. Performance testing was done on a DD2.1 using only the stop0 idle state (the shallowest state which supports state loss), using context_switch selftest configured to ping-poing between two threads on the same core and two different cores. Performance improvement for same core is 7.0%, different cores is 14.8%. Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc: add POWER9_DD20 featureNicholas Piggin2017-11-062-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cc: Michael Neuling <mikey@neuling.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc: Remove facility loadups on transactional {fp, vec, vsx} unavailableCyril Bur2017-11-061-30/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After handling a transactional FP, Altivec or VSX unavailable exception. The return to userspace code will detect that the TIF_RESTORE_TM bit is set and call restore_tm_state(). restore_tm_state() will call restore_math() to ensure that the correct facilities are loaded. This means that all the loadup code in {fp,altivec,vsx}_unavailable_tm() is doing pointless work and can simply be removed. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc: Always save/restore checkpointed regs during treclaim/trecheckpointCyril Bur2017-11-065-78/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Lazy save and restore of FP/Altivec means that a userspace process can be sent to userspace with FP or Altivec disabled and loaded only as required (by way of an FP/Altivec unavailable exception). Transactional Memory complicates this situation as a transaction could be started without FP/Altivec being loaded up. This causes the hardware to checkpoint incorrect registers. Handling FP/Altivec unavailable exceptions while a thread is transactional requires a reclaim and recheckpoint to ensure the CPU has correct state for both sets of registers. tm_reclaim() has optimisations to not always save the FP/Altivec registers to the checkpointed save area. This was originally done because the caller might have information that the checkpointed registers aren't valid due to lazy save and restore. We've also been a little vague as to how tm_reclaim() leaves the FP/Altivec state since it doesn't necessarily always save it to the thread struct. This has lead to an (incorrect) assumption that it leaves the checkpointed state on the CPU. tm_recheckpoint() has similar optimisations in reverse. It may not always reload the checkpointed FP/Altivec registers from the thread struct before the trecheckpoint. It is therefore quite unclear where it expects to get the state from. This didn't help with the assumption made about tm_reclaim(). These optimisations sit in what is by definition a slow path. If a process has to go through a reclaim/recheckpoint then its transaction will be doomed on returning to userspace. This mean that the process will be unable to complete its transaction and be forced to its failure handler. This is already an out if line case for userspace. Furthermore, the cost of copying 64 times 128 bits from registers isn't very long[0] (at all) on modern processors. As such it appears these optimisations have only served to increase code complexity and are unlikely to have had a measurable performance impact. Our transactional memory handling has been riddled with bugs. A cause of this has been difficulty in following the code flow, code complexity has not been our friend here. It makes sense to remove these optimisations in favour of a (hopefully) more stable implementation. This patch does mean that some times the assembly will needlessly save 'junk' registers which will subsequently get overwritten with the correct value by the C code which calls the assembly function. This small inefficiency is far outweighed by the reduction in complexity for general TM code, context switching paths, and transactional facility unavailable exception handler. 0: I tried to measure it once for other work and found that it was hiding in the noise of everything else I was working with. I find it exceedingly likely this will be the case here. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc: Force reload for recheckpoint during tm {fp, vec, vsx} unavailable ↵Cyril Bur2017-11-062-7/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | exception Lazy save and restore of FP/Altivec means that a userspace process can be sent to userspace with FP or Altivec disabled and loaded only as required (by way of an FP/Altivec unavailable exception). Transactional Memory complicates this situation as a transaction could be started without FP/Altivec being loaded up. This causes the hardware to checkpoint incorrect registers. Handling FP/Altivec unavailable exceptions while a thread is transactional requires a reclaim and recheckpoint to ensure the CPU has correct state for both sets of registers. tm_reclaim() has optimisations to not always save the FP/Altivec registers to the checkpointed save area. This was originally done because the caller might have information that the checkpointed registers aren't valid due to lazy save and restore. We've also been a little vague as to how tm_reclaim() leaves the FP/Altivec state since it doesn't necessarily always save it to the thread struct. This has lead to an (incorrect) assumption that it leaves the checkpointed state on the CPU. tm_recheckpoint() has similar optimisations in reverse. It may not always reload the checkpointed FP/Altivec registers from the thread struct before the trecheckpoint. It is therefore quite unclear where it expects to get the state from. This didn't help with the assumption made about tm_reclaim(). This patch is a minimal fix for ease of backporting. A more correct fix which removes the msr parameter to tm_reclaim() and tm_recheckpoint() altogether has been upstreamed to apply on top of this patch. Fixes: dc3106690b20 ("powerpc: tm: Always use fp_state and vr_state to store live registers") Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc: Don't enable FP/Altivec if not checkpointedCyril Bur2017-11-062-6/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Lazy save and restore of FP/Altivec means that a userspace process can be sent to userspace with FP or Altivec disabled and loaded only as required (by way of an FP/Altivec unavailable exception). Transactional Memory complicates this situation as a transaction could be started without FP/Altivec being loaded up. This causes the hardware to checkpoint incorrect registers. Handling FP/Altivec unavailable exceptions while a thread is transactional requires a reclaim and recheckpoint to ensure the CPU has correct state for both sets of registers. Lazy save and restore of FP/Altivec cannot be done if a process is transactional. If a facility was enabled it must remain enabled whenever a thread is transactional. Commit dc16b553c949 ("powerpc: Always restore FPU/VEC/VSX if hardware transactional memory in use") ensures that the facilities are always enabled if a thread is transactional. A bug in the introduced code may cause it to inadvertently enable a facility that was (and should remain) disabled. The problem with this extraneous enablement is that the registers for the erroneously enabled facility have not been correctly recheckpointed - the recheckpointing code assumed the facility would remain disabled. Further compounding the issue, the transactional {fp,altivec,vsx} unavailable code has been incorrectly using the MSR to enable facilities. The presence of the {FP,VEC,VSX} bit in the regs->msr simply means if the registers are live on the CPU, not if the kernel should load them before returning to userspace. This has worked due to the bug mentioned above. This causes transactional threads which return to their failure handler to observe incorrect checkpointed registers. Perhaps an example will help illustrate the problem: A userspace process is running and uses both FP and Altivec registers. This process then continues to run for some time without touching either sets of registers. The kernel subsequently disables the facilities as part of lazy save and restore. The userspace process then performs a tbegin and the CPU checkpoints 'junk' FP and Altivec registers. The process then performs a floating point instruction triggering a fp unavailable exception in the kernel. The kernel then loads the FP registers - and only the FP registers. Since the thread is transactional it must perform a reclaim and recheckpoint to ensure both the checkpointed registers and the transactional registers are correct. It then (correctly) enables MSR[FP] for the process. Later (on exception exist) the kernel also (inadvertently) enables MSR[VEC]. The process is then returned to userspace. Since the act of loading the FP registers doomed the transaction we know CPU will fail the transaction, restore its checkpointed registers, and return the process to its failure handler. The problem is that we're now running with Altivec enabled and the 'junk' checkpointed registers are restored. The kernel had only recheckpointed FP. This patch solves this by only activating FP/Altivec if userspace was using them when it entered the kernel and not simply if the process is transactional. Fixes: dc16b553c949 ("powerpc: Always restore FPU/VEC/VSX if hardware transactional memory in use") Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/eeh: Stop using do_gettimeofday()Arnd Bergmann2017-11-062-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This interface is inefficient and deprecated because of the y2038 overflow. ktime_get_seconds() is an appropriate replacement here, since it has sufficient granularity but is more efficient and uses monotonic time. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/tm: Don't check for WARN in TM Bad Thing handlingMichael Ellerman2017-11-061-7/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when we take a TM Bad Thing program check exception, we search the bug table to see if the program check was generated by a WARN/WARN_ON etc. That makes no sense, the WARN macros use trap instructions, which should never generate a TM Bad Thing exception. If they ever did that would be a bug and we should oops. We do have some hand-coded bugs in tm.S, using EMIT_BUG_ENTRY, but those are all BUGs not WARNs, and they all use trap instructions anyway. Almost certainly this check was incorrectly copied from the REASON_TRAP handling in the same function. Remove it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-By: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64Michael Ellerman2017-11-0610-29/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CONFIG_PPC_STD_MMU_64 indicates support for the "standard" powerpc MMU on 64-bit CPUs. The "standard" MMU refers to the hash page table MMU found in "server" processors, from IBM mainly. Currently CONFIG_PPC_STD_MMU_64 is == CONFIG_PPC_BOOK3S_64. While it's annoying to have two symbols that always have the same value, it's not quite annoying enough to bother removing one. However with the arrival of Power9, we now have the situation where CONFIG_PPC_STD_MMU_64 is enabled, but the kernel is running using the Radix MMU - *not* the "standard" MMU. So it is now actively confusing to use it, because it implies that code is disabled or inactive when the Radix MMU is in use, however that is not necessarily true. So s/CONFIG_PPC_STD_MMU_64/CONFIG_PPC_BOOK3S_64/, and do some minor formatting updates of some of the affected lines. This will be a pain for backports, but c'est la vie. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/64: Free up CPU_FTR_ICSWXMichael Ellerman2017-11-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The last user of CPU_FTR_ICSWX was removed in commit 6ff4d3e96652 ("powerpc: Remove old unused icswx based coprocessor support"), so free the bit up for future use. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/64: Fix latency tracing for lazy irq replayNicholas Piggin2017-11-061-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When returning from an exception to a soft-enabled context, pending IRQs are replayed but IRQ tracing is not reset, so a number of them can get chained together into the same IRQ-disabled trace. Fix this by having __check_irq_replay re-set IRQ trace. This is conceptually where we respond to the next interrupt, so it fits the semantics of the IRQ tracer. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | KVM: PPC: Book3S HV: Handle host system reset in guest modeNicholas Piggin2017-11-062-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the host takes a system reset interrupt while a guest is running, the CPU must exit the guest before processing the host exception handler. After this patch, taking a sysrq+x with a CPU running in a guest gives a trace like this: cpu 0x27: Vector: 100 (System Reset) at [c000000fdf5776f0] pc: c008000010158b80: kvmppc_run_core+0x16b8/0x1ad0 [kvm_hv] lr: c008000010158b80: kvmppc_run_core+0x16b8/0x1ad0 [kvm_hv] sp: c000000fdf577850 msr: 9000000002803033 current = 0xc000000fdf4b1e00 paca = 0xc00000000fd4d680 softe: 3 irq_happened: 0x01 pid = 6608, comm = qemu-system-ppc Linux version 4.14.0-rc7-01489-g47e1893a404a-dirty #26 SMP [c000000fdf577a00] c008000010159dd4 kvmppc_vcpu_run_hv+0x3dc/0x12d0 [kvm_hv] [c000000fdf577b30] c0080000100a537c kvmppc_vcpu_run+0x44/0x60 [kvm] [c000000fdf577b60] c0080000100a1ae0 kvm_arch_vcpu_ioctl_run+0x118/0x310 [kvm] [c000000fdf577c00] c008000010093e98 kvm_vcpu_ioctl+0x530/0x7c0 [kvm] [c000000fdf577d50] c000000000357bf8 do_vfs_ioctl+0xd8/0x8c0 [c000000fdf577df0] c000000000358448 SyS_ioctl+0x68/0x100 [c000000fdf577e30] c00000000000b220 system_call+0x58/0x6c --- Exception: c01 (System Call) at 00007fff76868df0 SP (7fff7069baf0) is in userspace Fixes: e36d0a2ed5 ("powerpc/powernv: Implement NMI IPI with OPAL_SIGNAL_SYSTEM_RESET") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc: Disable the fast-endian switch syscall by defaultMichael Ellerman2017-10-221-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Back in 2008 we added support for "fast little-endian switch" in the syscall path. This added a special case syscall number 0x1ebe, which is caught very early in the system call exception and switches endian with as little overhead as possible. See commit 745a14cc264b ("[POWERPC] Add fast little-endian switch system call") for full details. Although it is fast, it's also completely non standard. The "syscall number" is out of the range of normal syscalls, it can't be traced or audited, and it's a bit of a wart. To the best of our knowledge it was only used by one program, now long since discontinued. So in an effort to shake out any current users, put it behind a config option, and make it default n. If anyone *is* using it they can quickly reinstate it with a rebuild, and we can flip it to default y. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/64s: Move the two FAST_ENDIAN macros next to each otherMichael Ellerman2017-10-221-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So we can #ifdef them in the next patch. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/tm: P9 disable transactionally suspended sigcontextsMichael Neuling2017-10-213-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unfortunately userspace can construct a sigcontext which enables suspend. Thus userspace can force Linux into a path where trechkpt is executed. This patch blocks this from happening on POWER9 by sanity checking sigcontexts passed in. ptrace doesn't have this problem as only MSR SE and BE can be changed via ptrace. This patch also adds a number of WARN_ON()s in case we ever enter suspend when we shouldn't. This should not happen, but if it does the symptoms are soft lockup warnings which are not obviously TM related, so the WARN_ON()s should make it obvious what's happening. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/powernv: Enable TM without suspend if possibleMichael Ellerman2017-10-212-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some Power9 revisions can run in a mode where TM operates without suspended state. If we find ourself on a CPU that might be in this mode, we query OPAL to check, and if so we reenable TM in CPU features, and enable a new user feature to signal to userspace that we are in this mode. We do not enable the "normal" user feature, PPC_FEATURE2_HTM, but we do enable PPC_FEATURE2_HTM_NOSC because that indicates to userspace that the kernel will abort transactions on syscall entry, which is true regardless of the suspend mode. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | | | powerpc/tm: Add commandline option to disable hardware transactional memoryCyril Bur2017-10-201-0/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the kernel relies on firmware to inform it whether or not the CPU supports HTM and as long as the kernel was built with CONFIG_PPC_TRANSACTIONAL_MEM=y then it will allow userspace to make use of the facility. There may be situations where it would be advantageous for the kernel to not allow userspace to use HTM, currently the only way to achieve this is to recompile the kernel with CONFIG_PPC_TRANSACTIONAL_MEM=n. This patch adds a simple commandline option so that HTM can be disabled at boot time. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> [mpe: Simplify to a bool, move to prom.c, put doco in the right place. Always disable, regardless of initial state, to avoid user confusion.] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>