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* Merge branch 'irq/urgent' into x86/apicThomas Gleixner2017-10-1238-494/+561
|\ | | | | | | Pick up core changes which affect the vector rework.
| * Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2017-10-065-9/+18
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM fixes from Radim Krčmář: - fix PPC XIVE interrupt delivery - fix x86 RCU breakage from asynchronous page faults when built without PREEMPT_COUNT - fix x86 build with -frecord-gcc-switches - fix x86 build without X86_LOCAL_APIC * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: add X86_LOCAL_APIC dependency x86/kvm: Move kvm_fastop_exception to .fixup section kvm/x86: Avoid async PF preempting the kernel incorrectly KVM: PPC: Book3S: Fix server always zero from kvmppc_xive_get_xive()
| | * KVM: add X86_LOCAL_APIC dependencyArnd Bergmann2017-10-051-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The rework of the posted interrupt handling broke building without support for the local APIC: ERROR: "boot_cpu_physical_apicid" [arch/x86/kvm/kvm-intel.ko] undefined! That configuration is probably not particularly useful anyway, so we can avoid the randconfig failures by adding a Kconfig dependency. Fixes: 8b306e2f3c41 ("KVM: VMX: avoid double list add with VT-d posted interrupts") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
| | * x86/kvm: Move kvm_fastop_exception to .fixup sectionJosh Poimboeuf2017-10-051-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When compiling the kernel with the '-frecord-gcc-switches' flag, objtool complains: arch/x86/kvm/emulate.o: warning: objtool: .GCC.command.line+0x0: special: can't find new instruction And also the kernel fails to link. The problem is that the 'kvm_fastop_exception' code gets placed into the throwaway '.GCC.command.line' section instead of '.text'. Exception fixup code is conventionally placed in the '.fixup' section, so put it there where it belongs. Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
| | * kvm/x86: Avoid async PF preempting the kernel incorrectlyBoqun Feng2017-10-043-7/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, in PREEMPT_COUNT=n kernel, kvm_async_pf_task_wait() could call schedule() to reschedule in some cases. This could result in accidentally ending the current RCU read-side critical section early, causing random memory corruption in the guest, or otherwise preempting the currently running task inside between preempt_disable and preempt_enable. The difficulty to handle this well is because we don't know whether an async PF delivered in a preemptible section or RCU read-side critical section for PREEMPT_COUNT=n, since preempt_disable()/enable() and rcu_read_lock/unlock() are both no-ops in that case. To cure this, we treat any async PF interrupting a kernel context as one that cannot be preempted, preventing kvm_async_pf_task_wait() from choosing the schedule() path in that case. To do so, a second parameter for kvm_async_pf_task_wait() is introduced, so that we know whether it's called from a context interrupting the kernel, and the parameter is set properly in all the callsites. Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: stable@vger.kernel.org Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
| * | Merge branch 'core-watchdog-for-linus' of ↵Linus Torvalds2017-10-061-7/+4
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull watchddog clean-up and fixes from Thomas Gleixner: "The watchdog (hard/softlockup detector) code is pretty much broken in its current state. The patch series addresses this by removing all duct tape and refactoring it into a workable state. The reasons why I ask for inclusion that late in the cycle are: 1) The code causes lockdep splats vs. hotplug locking which get reported over and over. Unfortunately there is no easy fix. 2) The risk of breakage is minimal because it's already broken 3) As 4.14 is a long term stable kernel, I prefer to have working watchdog code in that and the lockdep issues resolved. I wouldn't ask you to pull if 4.14 wouldn't be a LTS kernel or if the solution would be easy to backport. 4) The series was around before the merge window opened, but then got delayed due to the UP failure caused by the for_each_cpu() surprise which we discussed recently. Changes vs. V1: - Addressed your review points - Addressed the warning in the powerpc code which was discovered late - Changed two function names which made sense up to a certain point in the series. Now they match what they do in the end. - Fixed a 'unused variable' warning, which got not detected by the intel robot. I triggered it when trying all possible related config combinations manually. Randconfig testing seems not random enough. The changes have been tested by and reviewed by Don Zickus and tested and acked by Micheal Ellerman for powerpc" * 'core-watchdog-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) watchdog/core: Put softlockup_threads_initialized under ifdef guard watchdog/core: Rename some softlockup_* functions powerpc/watchdog: Make use of watchdog_nmi_probe() watchdog/core, powerpc: Lock cpus across reconfiguration watchdog/core, powerpc: Replace watchdog_nmi_reconfigure() watchdog/hardlockup/perf: Fix spelling mistake: "permanetely" -> "permanently" watchdog/hardlockup/perf: Cure UP damage watchdog/hardlockup: Clean up hotplug locking mess watchdog/hardlockup/perf: Simplify deferred event destroy watchdog/hardlockup/perf: Use new perf CPU enable mechanism watchdog/hardlockup/perf: Implement CPU enable replacement watchdog/hardlockup/perf: Implement init time detection of perf watchdog/hardlockup/perf: Implement init time perf validation watchdog/core: Get rid of the racy update loop watchdog/core, powerpc: Make watchdog_nmi_reconfigure() two stage watchdog/sysctl: Clean up sysctl variable name space watchdog/sysctl: Get rid of the #ifdeffery watchdog/core: Clean up header mess watchdog/core: Further simplify sysctl handling watchdog/core: Get rid of the thread teardown/setup dance ...
| | * | perf/x86/intel, watchdog/core: Sanitize PMU HT bug workaroundPeter Zijlstra2017-09-141-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The lockup_detector_suspend/resume() interface is broken in several ways especially as it results in recursive locking of the CPU hotplug lock. Use the new stop/restart interface in the perf NMI watchdog to temporarily disable and reenable the already active watchdog events. That's enough to handle it. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Don Zickus <dzickus@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Ulrich Obergfell <uobergfe@redhat.com> Link: http://lkml.kernel.org/r/20170912194146.247141871@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2017-10-051-2/+2
| |\ \ \ | | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking fixes from David Miller: 1) Check iwlwifi 9000 reorder buffer out-of-space condition properly, from Sara Sharon. 2) Fix RCU splat in qualcomm rmnet driver, from Subash Abhinov Kasiviswanathan. 3) Fix session and tunnel release races in l2tp, from Guillaume Nault and Sabrina Dubroca. 4) Fix endian bug in sctp_diag_dump(), from Dan Carpenter. 5) Several mlx5 driver fixes from the Mellanox folks (max flow counters cap check, invalid memory access in IPoIB support, etc.) 6) tun_get_user() should bail if skb->len is zero, from Alexander Potapenko. 7) Fix RCU lookups in inetpeer, from Eric Dumazet. 8) Fix locking in packet_do_bund(). 9) Handle cb->start() error properly in netlink dump code, from Jason A. Donenfeld. 10) Handle multicast properly in UDP socket early demux code. From Paolo Abeni. 11) Several erspan bug fixes in ip_gre, from Xin Long. 12) Fix use-after-free in socket filter code, in order to handle the fact that listener lock is no longer taken during the three-way TCP handshake. From Eric Dumazet. 13) Fix infoleak in RTM_GETSTATS, from Nikolay Aleksandrov. 14) Fix tail call generation in x86-64 BPF JIT, from Alexei Starovoitov. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (77 commits) net: 8021q: skip packets if the vlan is down bpf: fix bpf_tail_call() x64 JIT net: stmmac: dwmac-rk: Add RK3128 GMAC support rndis_host: support Novatel Verizon USB730L net: rtnetlink: fix info leak in RTM_GETSTATS call socket, bpf: fix possible use after free mlxsw: spectrum_router: Track RIF of IPIP next hops mlxsw: spectrum_router: Move VRF refcounting net: hns3: Fix an error handling path in 'hclge_rss_init_hw()' net: mvpp2: Fix clock resource by adding an optional bus clock r8152: add Linksys USB3GIGV1 id l2tp: fix l2tp_eth module loading ip_gre: erspan device should keep dst ip_gre: set tunnel hlen properly in erspan_tunnel_init ip_gre: check packet length and mtu correctly in erspan_xmit ip_gre: get key from session_id correctly in erspan_rcv tipc: use only positive error codes in messages ppp: fix __percpu annotation udp: perform source validation for mcast early demux IPv4: early demux can return an error code ...
| | * | bpf: fix bpf_tail_call() x64 JITAlexei Starovoitov2017-10-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - bpf prog_array just like all other types of bpf array accepts 32-bit index. Clarify that in the comment. - fix x64 JIT of bpf_tail_call which was incorrectly loading 8 instead of 4 bytes - tighten corresponding check in the interpreter to stay consistent The JIT bug can be triggered after introduction of BPF_F_NUMA_NODE flag in commit 96eabe7a40aa in 4.14. Before that the map_flags would stay zero and though JIT code is wrong it will check bounds correctly. Hence two fixes tags. All other JITs don't have this problem. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Fixes: 96eabe7a40aa ("bpf: Allow selecting numa node during map creation") Fixes: b52f00e6a715 ("x86: bpf_jit: implement bpf_tail_call() helper") Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2017-10-0113-46/+55
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "This contains the following fixes and improvements: - Avoid dereferencing an unprotected VMA pointer in the fault signal generation code - Fix inline asm call constraints for GCC 4.4 - Use existing register variable to retrieve the stack pointer instead of forcing the compiler to create another indirect access which results in excessive extra 'mov %rsp, %<dst>' instructions - Disable branch profiling for the memory encryption code to prevent an early boot crash - Fix a sparse warning caused by casting the __user annotation in __get_user_asm_u64() away - Fix an off by one error in the loop termination of the error patch in the x86 sysfs init code - Add missing CPU IDs to various Intel specific drivers to enable the functionality on recent hardware - More (init) constification in the numachip code" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/asm: Use register variable to get stack pointer value x86/mm: Disable branch profiling in mem_encrypt.c x86/asm: Fix inline asm call constraints for GCC 4.4 perf/x86/intel/uncore: Correct num_boxes for IIO and IRP perf/x86/intel/rapl: Add missing CPU IDs perf/x86/msr: Add missing CPU IDs perf/x86/intel/cstate: Add missing CPU IDs x86: Don't cast away the __user in __get_user_asm_u64() x86/sysfs: Fix off-by-one error in loop termination x86/mm: Fix fault error path using unsafe vma pointer x86/numachip: Add const and __initconst to numachip2_clockevent
| | * | | x86/asm: Use register variable to get stack pointer valueAndrey Ryabinin2017-09-295-18/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we use current_stack_pointer() function to get the value of the stack pointer register. Since commit: f5caf621ee35 ("x86/asm: Fix inline asm call constraints for Clang") ... we have a stack register variable declared. It can be used instead of current_stack_pointer() function which allows to optimize away some excessive "mov %rsp, %<dst>" instructions: -mov %rsp,%rdx -sub %rdx,%rax -cmp $0x3fff,%rax -ja ffffffff810722fd <ist_begin_non_atomic+0x2d> +sub %rsp,%rax +cmp $0x3fff,%rax +ja ffffffff810722fa <ist_begin_non_atomic+0x2a> Remove current_stack_pointer(), rename __asm_call_sp to current_stack_pointer and use it instead of the removed function. Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170929141537.29167-1-aryabinin@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | x86/mm: Disable branch profiling in mem_encrypt.cTom Lendacky2017-09-291-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some routines in mem_encrypt.c are called very early in the boot process, e.g. sme_encrypt_kernel(). When CONFIG_TRACE_BRANCH_PROFILING=y is defined the resulting branch profiling associated with the check to see if SME is active results in a kernel crash. Disable branch profiling for mem_encrypt.c by defining DISABLE_BRANCH_PROFILING before including any header files. Reported-by: kernel test robot <lkp@01.org> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Acked-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170929162419.6016.53390.stgit@tlendack-t1.amdoffice.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | x86/asm: Fix inline asm call constraints for GCC 4.4Josh Poimboeuf2017-09-291-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel test bot (run by Xiaolong Ye) reported that the following commit: f5caf621ee35 ("x86/asm: Fix inline asm call constraints for Clang") is causing double faults in a kernel compiled with GCC 4.4. Linus subsequently diagnosed the crash pattern and the buggy commit and found that the issue is with this code: register unsigned int __asm_call_sp asm("esp"); #define ASM_CALL_CONSTRAINT "+r" (__asm_call_sp) Even on a 64-bit kernel, it's using ESP instead of RSP. That causes GCC to produce the following bogus code: ffffffff8147461d: 89 e0 mov %esp,%eax ffffffff8147461f: 4c 89 f7 mov %r14,%rdi ffffffff81474622: 4c 89 fe mov %r15,%rsi ffffffff81474625: ba 20 00 00 00 mov $0x20,%edx ffffffff8147462a: 89 c4 mov %eax,%esp ffffffff8147462c: e8 bf 52 05 00 callq ffffffff814c98f0 <copy_user_generic_unrolled> Despite the absurdity of it backing up and restoring the stack pointer for no reason, the bug is actually the fact that it's only backing up and restoring the lower 32 bits of the stack pointer. The upper 32 bits are getting cleared out, corrupting the stack pointer. So change the '__asm_call_sp' register variable to be associated with the actual full-size stack pointer. This also requires changing the __ASM_SEL() macro to be based on the actual compiled arch size, rather than the CONFIG value, because CONFIG_X86_64 compiles some files with '-m32' (e.g., realmode and vdso). Otherwise Clang fails to build the kernel because it complains about the use of a 64-bit register (RSP) in a 32-bit file. Reported-and-Bisected-and-Tested-by: kernel test robot <xiaolong.ye@intel.com> Diagnosed-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: LKP <lkp@01.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthias Kaehlcke <mka@chromium.org> Cc: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: f5caf621ee35 ("x86/asm: Fix inline asm call constraints for Clang") Link: http://lkml.kernel.org/r/20170928215826.6sdpmwtkiydiytim@treble Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | perf/x86/intel/uncore: Correct num_boxes for IIO and IRPKan Liang2017-09-251-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are 6 IIO/IRP boxes for CBDMA, PCIe0-2, MCP 0 and MCP 1 separately. Correct the num_boxes. Signed-off-by: Kan Liang <Kan.liang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: eranian@google.com Cc: acme@kernel.org Link: http://lkml.kernel.org/r/1505149816-12580-1-git-send-email-kan.liang@intel.com
| | * | | perf/x86/intel/rapl: Add missing CPU IDsKan Liang2017-09-251-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DENVERTON and GEMINI_LAKE support same RAPL counters as Apollo Lake. Signed-off-by: Kan Liang <Kan.liang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: piotr.luc@intel.com Cc: harry.pan@intel.com Cc: srinivas.pandruvada@linux.intel.com Link: http://lkml.kernel.org/r/20170908213449.6224-3-kan.liang@intel.com
| | * | | perf/x86/msr: Add missing CPU IDsKan Liang2017-09-251-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Goldmont, Glodmont plus and Xeon Phi have MSR_SMI_COUNT as well. Signed-off-by: Kan Liang <Kan.liang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: piotr.luc@intel.com Cc: harry.pan@intel.com Cc: srinivas.pandruvada@linux.intel.com Link: http://lkml.kernel.org/r/20170908213449.6224-2-kan.liang@intel.com
| | * | | perf/x86/intel/cstate: Add missing CPU IDsKan Liang2017-09-251-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Skylake server uses the same C-state residency events as Sandy Bridge. Denverton and Gemini lake use the same C-state residency events as Apollo Lake. Signed-off-by: Kan Liang <Kan.liang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: piotr.luc@intel.com Cc: harry.pan@intel.com Cc: srinivas.pandruvada@linux.intel.com Link: http://lkml.kernel.org/r/20170908213449.6224-1-kan.liang@intel.com
| | * | | x86: Don't cast away the __user in __get_user_asm_u64()Ville Syrjälä2017-09-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't cast away the __user in __get_user_asm_u64() on x86-32. Prevents sparse getting upset. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin LaHaise <bcrl@kvack.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170912164000.13745-1-ville.syrjala@linux.intel.com
| | * | | x86/sysfs: Fix off-by-one error in loop terminationSean Fu2017-09-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An off-by-one error in loop terminantion conditions in create_setup_data_nodes() will lead to memory leak when create_setup_data_node() failed. Signed-off-by: Sean Fu <fxinrong@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1505090001-1157-1-git-send-email-fxinrong@gmail.com
| | * | | x86/mm: Fix fault error path using unsafe vma pointerLaurent Dufour2017-09-251-23/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7b2d0dbac489 ("x86/mm/pkeys: Pass VMA down in to fault signal generation code") passes down a vma pointer to the error path, but that is done once the mmap_sem is released when calling mm_fault_error() from __do_page_fault(). This is dangerous as the vma structure is no more safe to be used once the mmap_sem has been released. As only the protection key value is required in the error processing, we could just pass down this value. Fix it by passing a pointer to a protection key value down to the fault signal generation code. The use of a pointer allows to keep the check generating a warning message in fill_sig_info_pkey() when the vma was not known. If the pointer is valid, the protection value can be accessed by deferencing the pointer. [ tglx: Made *pkey u32 as that's the type which is passed in siginfo ] Fixes: 7b2d0dbac489 ("x86/mm/pkeys: Pass VMA down in to fault signal generation code") Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1504513935-12742-1-git-send-email-ldufour@linux.vnet.ibm.com
| * | | | Merge tag 'for-linus-4.14c-rc3-tag' of ↵Linus Torvalds2017-09-292-11/+6
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - avoid a warning when compiling with clang - consider read-only bits in xen-pciback when writing to a BAR - fix a boot crash of pv-domains * tag 'for-linus-4.14c-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/mmu: Call xen_cleanhighmap() with 4MB aligned for page tables mapping xen-pciback: relax BAR sizing write value check x86/xen: clean up clang build warning
| | * | | | xen/mmu: Call xen_cleanhighmap() with 4MB aligned for page tables mappingZhenzhong Duan2017-09-281-9/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When bootup a PVM guest with large memory(Ex.240GB), XEN provided initial mapping overlaps with kernel module virtual space. When mapping in this space is cleared by xen_cleanhighmap(), in certain case there could be an 2MB mapping left. This is due to XEN initialize 4MB aligned mapping but xen_cleanhighmap() finish at 2MB boundary. When module loading is just on top of the 2MB space, got below warning: WARNING: at mm/vmalloc.c:106 vmap_pte_range+0x14e/0x190() Call Trace: [<ffffffff81117083>] warn_alloc_failed+0xf3/0x160 [<ffffffff81146022>] __vmalloc_area_node+0x182/0x1c0 [<ffffffff810ac91e>] ? module_alloc_update_bounds+0x1e/0x80 [<ffffffff81145df7>] __vmalloc_node_range+0xa7/0x110 [<ffffffff810ac91e>] ? module_alloc_update_bounds+0x1e/0x80 [<ffffffff8103ca54>] module_alloc+0x64/0x70 [<ffffffff810ac91e>] ? module_alloc_update_bounds+0x1e/0x80 [<ffffffff810ac91e>] module_alloc_update_bounds+0x1e/0x80 [<ffffffff810ac9a7>] move_module+0x27/0x150 [<ffffffff810aefa0>] layout_and_allocate+0x120/0x1b0 [<ffffffff810af0a8>] load_module+0x78/0x640 [<ffffffff811ff90b>] ? security_file_permission+0x8b/0x90 [<ffffffff810af6d2>] sys_init_module+0x62/0x1e0 [<ffffffff815154c2>] system_call_fastpath+0x16/0x1b Then the mapping of 2MB is cleared, finally oops when the page in that space is accessed. BUG: unable to handle kernel paging request at ffff880022600000 IP: [<ffffffff81260877>] clear_page_c_e+0x7/0x10 PGD 1788067 PUD 178c067 PMD 22434067 PTE 0 Oops: 0002 [#1] SMP Call Trace: [<ffffffff81116ef7>] ? prep_new_page+0x127/0x1c0 [<ffffffff81117d42>] get_page_from_freelist+0x1e2/0x550 [<ffffffff81133010>] ? ii_iovec_copy_to_user+0x90/0x140 [<ffffffff81119c9d>] __alloc_pages_nodemask+0x12d/0x230 [<ffffffff81155516>] alloc_pages_vma+0xc6/0x1a0 [<ffffffff81006ffd>] ? pte_mfn_to_pfn+0x7d/0x100 [<ffffffff81134cfb>] do_anonymous_page+0x16b/0x350 [<ffffffff81139c34>] handle_pte_fault+0x1e4/0x200 [<ffffffff8100712e>] ? xen_pmd_val+0xe/0x10 [<ffffffff810052c9>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e [<ffffffff81139dab>] handle_mm_fault+0x15b/0x270 [<ffffffff81510c10>] do_page_fault+0x140/0x470 [<ffffffff8150d7d5>] page_fault+0x25/0x30 Call xen_cleanhighmap() with 4MB aligned for page tables mapping to fix it. The unnecessory call of xen_cleanhighmap() in DEBUG mode is also removed. -v2: add comment about XEN alignment from Juergen. References: https://lists.xen.org/archives/html/xen-devel/2012-07/msg01562.html Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> [boris: added 'xen/mmu' tag to commit subject] Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
| | * | | | x86/xen: clean up clang build warningColin Ian King2017-09-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the case where sizeof(maddr) != sizeof(long) p is initialized and never read and clang throws a warning on this. Move declaration of p to clean up the clang build warning: warning: Value stored to 'p' during its initialization is never read Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
| * | | | | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2017-09-292-106/+103
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm fixes from Paolo Bonzini: "Mixed bugfixes. Perhaps the most interesting one is a latent bug that was finally triggered by PCID support" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: kvm/x86: Handle async PF in RCU read-side critical sections KVM: nVMX: Fix nested #PF intends to break L1's vmlauch/vmresume KVM: VMX: use cmpxchg64 KVM: VMX: simplify and fix vmx_vcpu_pi_load KVM: VMX: avoid double list add with VT-d posted interrupts KVM: VMX: extract __pi_post_block KVM: PPC: Book3S HV: Check for updated HDSISR on P9 HDSI exception KVM: nVMX: fix HOST_CR3/HOST_CR4 cache
| | * | | | | kvm/x86: Handle async PF in RCU read-side critical sectionsBoqun Feng2017-09-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sasha Levin reported a WARNING: | WARNING: CPU: 0 PID: 6974 at kernel/rcu/tree_plugin.h:329 | rcu_preempt_note_context_switch kernel/rcu/tree_plugin.h:329 [inline] | WARNING: CPU: 0 PID: 6974 at kernel/rcu/tree_plugin.h:329 | rcu_note_context_switch+0x16c/0x2210 kernel/rcu/tree.c:458 ... | CPU: 0 PID: 6974 Comm: syz-fuzzer Not tainted 4.13.0-next-20170908+ #246 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS | 1.10.1-1ubuntu1 04/01/2014 | Call Trace: ... | RIP: 0010:rcu_preempt_note_context_switch kernel/rcu/tree_plugin.h:329 [inline] | RIP: 0010:rcu_note_context_switch+0x16c/0x2210 kernel/rcu/tree.c:458 | RSP: 0018:ffff88003b2debc8 EFLAGS: 00010002 | RAX: 0000000000000001 RBX: 1ffff1000765bd85 RCX: 0000000000000000 | RDX: 1ffff100075d7882 RSI: ffffffffb5c7da20 RDI: ffff88003aebc410 | RBP: ffff88003b2def30 R08: dffffc0000000000 R09: 0000000000000001 | R10: 0000000000000000 R11: 0000000000000000 R12: ffff88003b2def08 | R13: 0000000000000000 R14: ffff88003aebc040 R15: ffff88003aebc040 | __schedule+0x201/0x2240 kernel/sched/core.c:3292 | schedule+0x113/0x460 kernel/sched/core.c:3421 | kvm_async_pf_task_wait+0x43f/0x940 arch/x86/kernel/kvm.c:158 | do_async_page_fault+0x72/0x90 arch/x86/kernel/kvm.c:271 | async_page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1069 | RIP: 0010:format_decode+0x240/0x830 lib/vsprintf.c:1996 | RSP: 0018:ffff88003b2df520 EFLAGS: 00010283 | RAX: 000000000000003f RBX: ffffffffb5d1e141 RCX: ffff88003b2df670 | RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffffffffb5d1e140 | RBP: ffff88003b2df560 R08: dffffc0000000000 R09: 0000000000000000 | R10: ffff88003b2df718 R11: 0000000000000000 R12: ffff88003b2df5d8 | R13: 0000000000000064 R14: ffffffffb5d1e140 R15: 0000000000000000 | vsnprintf+0x173/0x1700 lib/vsprintf.c:2136 | sprintf+0xbe/0xf0 lib/vsprintf.c:2386 | proc_self_get_link+0xfb/0x1c0 fs/proc/self.c:23 | get_link fs/namei.c:1047 [inline] | link_path_walk+0x1041/0x1490 fs/namei.c:2127 ... This happened when the host hit a page fault, and delivered it as in an async page fault, while the guest was in an RCU read-side critical section. The guest then tries to reschedule in kvm_async_pf_task_wait(), but rcu_preempt_note_context_switch() would treat the reschedule as a sleep in RCU read-side critical section, which is not allowed (even in preemptible RCU). Thus the WARN. To cure this, make kvm_async_pf_task_wait() go to the halt path if the PF happens in a RCU read-side critical section. Reported-by: Sasha Levin <levinsasha928@gmail.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | KVM: nVMX: Fix nested #PF intends to break L1's vmlauch/vmresumeWanpeng Li2017-09-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ------------[ cut here ]------------ WARNING: CPU: 4 PID: 5280 at /home/kernel/linux/arch/x86/kvm//vmx.c:11394 nested_vmx_vmexit+0xc2b/0xd70 [kvm_intel] CPU: 4 PID: 5280 Comm: qemu-system-x86 Tainted: G W OE 4.13.0+ #17 RIP: 0010:nested_vmx_vmexit+0xc2b/0xd70 [kvm_intel] Call Trace: ? emulator_read_emulated+0x15/0x20 [kvm] ? segmented_read+0xae/0xf0 [kvm] vmx_inject_page_fault_nested+0x60/0x70 [kvm_intel] ? vmx_inject_page_fault_nested+0x60/0x70 [kvm_intel] x86_emulate_instruction+0x733/0x810 [kvm] vmx_handle_exit+0x2f4/0xda0 [kvm_intel] ? kvm_arch_vcpu_ioctl_run+0xd2f/0x1c60 [kvm] kvm_arch_vcpu_ioctl_run+0xdab/0x1c60 [kvm] ? kvm_arch_vcpu_load+0x62/0x230 [kvm] kvm_vcpu_ioctl+0x340/0x700 [kvm] ? kvm_vcpu_ioctl+0x340/0x700 [kvm] ? __fget+0xfc/0x210 do_vfs_ioctl+0xa4/0x6a0 ? __fget+0x11d/0x210 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x23/0xc2 A nested #PF is triggered during L0 emulating instruction for L2. However, it doesn't consider we should not break L1's vmlauch/vmresme. This patch fixes it by queuing the #PF exception instead ,requesting an immediate VM exit from L2 and keeping the exception for L1 pending for a subsequent nested VM exit. This should actually work all the time, making vmx_inject_page_fault_nested totally unnecessary. However, that's not working yet, so this patch can work around the issue in the meanwhile. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | KVM: VMX: use cmpxchg64Paolo Bonzini2017-09-281-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a compilation failure on 32-bit systems. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | KVM: VMX: simplify and fix vmx_vcpu_pi_loadPaolo Bonzini2017-09-271-33/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The simplify part: do not touch pi_desc.nv, we can set it when the VCPU is first created. Likewise, pi_desc.sn is only handled by vmx_vcpu_pi_load, do not touch it in __pi_post_block. The fix part: do not check kvm_arch_has_assigned_device, instead check the SN bit to figure out whether vmx_vcpu_pi_put ran before. This matches what the previous patch did in pi_post_block. Cc: Huangweidong <weidong.huang@huawei.com> Cc: Gonglei <arei.gonglei@huawei.com> Cc: wangxin <wangxinxin.wang@huawei.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Tested-by: Longpeng (Mike) <longpeng2@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | KVM: VMX: avoid double list add with VT-d posted interruptsPaolo Bonzini2017-09-271-37/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some cases, for example involving hot-unplug of assigned devices, pi_post_block can forget to remove the vCPU from the blocked_vcpu_list. When this happens, the next call to pi_pre_block corrupts the list. Fix this in two ways. First, check vcpu->pre_pcpu in pi_pre_block and WARN instead of adding the element twice in the list. Second, always do the list removal in pi_post_block if vcpu->pre_pcpu is set (not -1). The new code keeps interrupts disabled for the whole duration of pi_pre_block/pi_post_block. This is not strictly necessary, but easier to follow. For the same reason, PI.ON is checked only after the cmpxchg, and to handle it we just call the post-block code. This removes duplication of the list removal code. Cc: Huangweidong <weidong.huang@huawei.com> Cc: Gonglei <arei.gonglei@huawei.com> Cc: wangxin <wangxinxin.wang@huawei.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Tested-by: Longpeng (Mike) <longpeng2@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | KVM: VMX: extract __pi_post_blockPaolo Bonzini2017-09-271-33/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Simple code movement patch, preparing for the next one. Cc: Huangweidong <weidong.huang@huawei.com> Cc: Gonglei <arei.gonglei@huawei.com> Cc: wangxin <wangxinxin.wang@huawei.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Tested-by: Longpeng (Mike) <longpeng2@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | KVM: nVMX: fix HOST_CR3/HOST_CR4 cacheLadi Prosek2017-09-221-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For nested virt we maintain multiple VMCS that can run on a vCPU. So it is incorrect to keep vmcs_host_cr3 and vmcs_host_cr4, whose purpose is caching the value of the rarely changing HOST_CR3 and HOST_CR4 VMCS fields, in vCPU-wide data structures. Hyper-V nested on KVM runs into this consistently for me with PCID enabled. CR3 is updated with a new value, unlikely(cr3 != vmx->host_state.vmcs_host_cr3) fires, and the currently loaded VMCS is updated. Then we switch from L2 to L1 and the next exit reverts CR3 to its old value. Fixes: d6e41f1151fe ("x86/mm, KVM: Teach KVM's VMX code that CR3 isn't a constant") Signed-off-by: Ladi Prosek <lprosek@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | | | Merge branch 'WIP.x86/fpu' into x86/fpu, because it's readyIngo Molnar2017-09-2615-315/+375
| |\ \ \ \ \ \ | | |_|_|/ / / | |/| | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Use using_compacted_format() instead of open coded X86_FEATURE_XSAVESEric Biggers2017-09-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the canonical method to use. Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-11-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Use validate_xstate_header() to validate the xstate_header in ↵Eric Biggers2017-09-261-11/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | copy_user_to_xstate() Tighten the checks in copy_user_to_xstate(). Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-10-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Eliminate the 'xfeatures' local variable in copy_user_to_xstate()Eric Biggers2017-09-261-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now have this field in hdr.xfeatures. Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-9-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Copy the full header in copy_user_to_xstate()Eric Biggers2017-09-261-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is in preparation to verify the full xstate header as supplied by user-space. Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-8-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Use validate_xstate_header() to validate the xstate_header in ↵Eric Biggers2017-09-261-10/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | copy_kernel_to_xstate() Tighten the checks in copy_kernel_to_xstate(). Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-7-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Eliminate the 'xfeatures' local variable in copy_kernel_to_xstate()Eric Biggers2017-09-261-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have this information in the xstate_header. Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-6-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Copy the full state_header in copy_kernel_to_xstate()Eric Biggers2017-09-261-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is in preparation to verify the full xstate header as supplied by user-space. Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-5-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Use validate_xstate_header() to validate the xstate_header in ↵Eric Biggers2017-09-261-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __fpu__restore_sig() Tighten the checks in __fpu__restore_sig() and update comments. Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-4-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Use validate_xstate_header() to validate the xstate_header in ↵Eric Biggers2017-09-261-13/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xstateregs_set() Tighten the checks in xstateregs_set(). Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-3-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Introduce validate_xstate_header()Eric Biggers2017-09-262-0/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move validation of user-supplied xstate_header into a helper function, in preparation of calling it from both the ptrace and sigreturn syscall paths. The new function also considers it to be an error if *any* reserved bits are set, whereas before we were just clearing most of them silently. This should reduce the chance of bugs that fail to correctly validate user-supplied XSAVE areas. It also will expose any broken userspace programs that set the other reserved bits; this is desirable because such programs will lose compatibility with future CPUs and kernels if those bits are ever used for anything. (There shouldn't be any such programs, and in fact in the case where the compacted format is in use we were already validating xfeatures. But you never know...) Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-2-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Rename fpu__activate_fpstate_read/write() to ↵Ingo Molnar2017-09-263-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fpu__prepare_[read|write]() As per the new nomenclature we don't 'activate' the FPU state anymore, we initialize it. So drop the _activate_fpstate name from these functions, which were a bit of a mouthful anyway, and name them: fpu__prepare_read() fpu__prepare_write() Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Rename fpu__activate_curr() to fpu__initialize()Ingo Molnar2017-09-265-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename this function to better express that it's all about initializing the FPU state of a task which goes hand in hand with the fpu::initialized field. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/20170923130016.21448-33-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Simplify and speed up fpu__copy()Ingo Molnar2017-09-261-12/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fpu__copy() has a preempt_disable()/enable() pair, which it had to do to be able to atomically unlazy the current task when doing an FNSAVE. But we don't unlazy tasks anymore, we always do direct saves/restores of FPU context. So remove both the unnecessary critical section, and update the comments. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/20170923130016.21448-32-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Fix stale comments about lazy FPU logicIngo Molnar2017-09-261-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't do any lazy restore anymore, what we have are two pieces of optimization: - no-FPU tasks that don't save/restore the FPU context (kernel threads are such) - cached FPU registers maintained via the fpu->last_cpu field. This means that if an FPU task context switches to a non-FPU task then we can maintain the FPU registers as an in-FPU copies (cache), and skip the restoration of them once we switch back to the original FPU-using task. Update all the comments that still referred to old 'lazy' and 'unlazy' concepts. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/20170923130016.21448-31-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Rename fpu::fpstate_active to fpu::initializedIngo Molnar2017-09-2611-35/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The x86 FPU code used to have a complex state machine where both the FPU registers and the FPU state context could be 'active' (or inactive) independently of each other - which enabled features like lazy FPU restore. Much of this complexity is gone in the current code: now we basically can have FPU-less tasks (kernel threads) that don't use (and save/restore) FPU state at all, plus full FPU users that save/restore directly with no laziness whatsoever. But the fpu::fpstate_active still carries bits of the old complexity - meanwhile this flag has become a simple flag that shows whether the FPU context saving area in the thread struct is initialized and used, or not. Rename it to fpu::initialized to express this simplicity in the name as well. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/20170923130016.21448-30-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Remove fpu__current_fpstate_write_begin/end()Ingo Molnar2017-09-262-65/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These functions are not used anymore, so remove them. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Bobby Powers <bobbypowers@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/20170923130016.21448-29-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Fix fpu__activate_fpstate_read() and update commentsIngo Molnar2017-09-261-7/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | fpu__activate_fpstate_read() can be called for the current task when coredumping - or for stopped tasks when ptrace-ing. Implement this properly in the code and update the comments. This also fixes an incorrect (but harmless) warning introduced by one of the earlier patches. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/20170923130016.21448-28-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/fpu: Reinitialize FPU registers if restoring FPU state failsEric Biggers2017-09-252-36/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Userspace can change the FPU state of a task using the ptrace() or rt_sigreturn() system calls. Because reserved bits in the FPU state can cause the XRSTOR instruction to fail, the kernel has to carefully validate that no reserved bits or other invalid values are being set. Unfortunately, there have been bugs in this validation code. For example, we were not checking that the 'xcomp_bv' field in the xstate_header was 0. As-is, such bugs are exploitable to read the FPU registers of other processes on the system. To do so, an attacker can create a task, assign to it an invalid FPU state, then spin in a loop and monitor the values of the FPU registers. Because the task's FPU registers are not being restored, sometimes the FPU registers will have the values from another process. This is likely to continue to be a problem in the future because the validation done by the CPU instructions like XRSTOR is not immediately visible to kernel developers. Nor will invalid FPU states ever be encountered during ordinary use --- they will only be seen during fuzzing or exploits. There can even be reserved bits outside the xstate_header which are easy to forget about. For example, the MXCSR register contains reserved bits, which were not validated by the KVM_SET_XSAVE ioctl until commit a575813bfe4b ("KVM: x86: Fix load damaged SSEx MXCSR register"). Therefore, mitigate this class of vulnerability by restoring the FPU registers from init_fpstate if restoring from the task's state fails. We actually used to do this, but it was (perhaps unwisely) removed by commit 9ccc27a5d297 ("x86/fpu: Remove error return values from copy_kernel_to_*regs() functions"). This new patch is also a bit different. First, it only clears the registers, not also the bad in-memory state; this is simpler and makes it easier to make the mitigation cover all callers of __copy_kernel_to_fpregs(). Second, it does the register clearing in an exception handler so that no extra instructions are added to context switches. In fact, we *remove* instructions, since previously we were always zeroing the register containing 'err' even if CONFIG_X86_DEBUG_FPU was disabled. Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170922174156.16780-4-ebiggers3@gmail.com Link: http://lkml.kernel.org/r/20170923130016.21448-27-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>