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* s390/ap: fix status returned by ap_qact()Halil Pasic2023-02-101-1/+4
| | | | | | | | | | | | | | Since commit 159491f3b509 ("s390/ap: rework assembler functions to use unions for in/out register variables") the function ap_qact() tries to grab the status from the wrong part of the register. Thus we always end up with zeros. Which is wrong, among others, because we detect failures via status.response_code. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reported-by: Harald Freudenberger <freude@linux.ibm.com> Fixes: 159491f3b509 ("s390/ap: rework assembler functions to use unions for in/out register variables") Reviewed-by: Harald Freudenberger <freude@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* s390/ap: fix status returned by ap_aqic()Halil Pasic2023-02-101-2/+5
| | | | | | | | | | | | | There function ap_aqic() tries to grab the status from the wrong part of the register. Thus we always end up with zeros. Which is wrong, among others, because we detect failures via status.response_code. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reported-by: Janosch Frank <frankja@linux.ibm.com> Fixes: 159491f3b509 ("s390/ap: rework assembler functions to use unions for in/out register variables") Reviewed-by: Harald Freudenberger <freude@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* Revert "s390/mem_detect: do not update output parameters on failure"Heiko Carstens2023-02-091-1/+4
| | | | | | | | | | | | | | | | | This reverts commit cbc29f107e51b1cc7d1e7b0bbe0691a1224205f1. Get rid of the following smatch warnings: arch/s390/include/asm/mem_detect.h:86 get_mem_detect_end() error: uninitialized symbol 'end'. arch/s390/include/asm/mem_detect.h:86 get_mem_detect_end() error: uninitialized symbol 'end'. arch/s390/boot/vmem.c:256 setup_vmem() error: uninitialized symbol 'start'. arch/s390/boot/vmem.c:258 setup_vmem() error: uninitialized symbol 'end'. Note that there is no bug in the code. This is purely to silence smatch. Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* s390/idle: remove arch_cpu_idle_time() and corresponding codeHeiko Carstens2023-02-093-74/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arch_cpu_idle_time() returns the idle time of any given cpu if it is in idle, or zero if not. All if this is racy and partially incorrect. Time stamps taken with store clock extended and store clock fast from different cpus are compared, while the architecture states that this is nothing which can be relied on (see Principles of Operation; Chapter 4, "Setting and Inspecting the Clock"). A more fundamental problem is that the timestamp when a cpu is leaving idle is taken early in the assembler part of the interrupt handler, and this value is only transferred many cycles later to the cpu's per-cpu idle data structure. This per cpu data structure is read by arch_cpu_idle() to tell for which period of time a remote cpu is idle: if only an idle_enter value is present, the assumed idle time of the cpu is calculated by taking a local timestamp and returning the difference of the local timestamp and the idle_enter value. This is potentially incorrect, since the remote cpu may have already left idle, but the taken timestamp may not have been transferred to the per-cpu data structure. This in turn means that too much idle time may be reported for a cpu, and a subsequent calculation of system idle time may result in a smaller value. Instead of coming up with even more complex code trying to fix this, just remove this code, and only account idle time of a cpu, after idle state is left. Another minor bug is that it is assumed that timestamps are non-zero, which is not necessarily the case for timestamps taken with store clock fast. This however is just a very minor problem, since this can only happen when the epoch increases. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* s390/vx: use simple assignments to access __vector128 membersHeiko Carstens2023-02-095-10/+10
| | | | | | | Use simple assignments to access __vector128 members instead of hard to read casts. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* s390/vx: add 64 and 128 bit members to __vector128 structHeiko Carstens2023-02-091-2/+9
| | | | | | | | | | | | | Add 64 and 128 bit members to __vector128 struct in order to allow reading of the complete value, or the higher or lower part of vector register contents instead of having to use casts. Add an explicit __aligned(4) statement to avoid that the alignment of the structure changes from 4 to 8. This should make sure that no breakage happens because of this change. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* s390/processor: always inline cpu flag helper functionsHeiko Carstens2023-02-091-4/+4
| | | | | | | | | | | | arch_cpu_idle() is marked noinstr and therefore must only call functions which are also not instrumented. Make sure that cpu flag helper functions are always inlined to avoid that the compiler generates an out-of-line function for e.g. the call within arch_cpu_idle(). Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* s390/idle: mark arch_cpu_idle() noinstrHeiko Carstens2023-02-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | linux-next commit ("cpuidle: tracing: Warn about !rcu_is_watching()") adds a new warning which hits on s390's arch_cpu_idle() function: RCU not on for: arch_cpu_idle+0x0/0x28 WARNING: CPU: 2 PID: 0 at include/linux/trace_recursion.h:162 arch_ftrace_ops_list_func+0x24c/0x258 Modules linked in: CPU: 2 PID: 0 Comm: swapper/2 Not tainted 6.2.0-rc6-next-20230202 #4 Hardware name: IBM 8561 T01 703 (z/VM 7.3.0) Krnl PSW : 0404d00180000000 00000000002b55c0 (arch_ftrace_ops_list_func+0x250/0x258) R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3 Krnl GPRS: c0000000ffffbfff 0000000080000002 0000000000000026 0000000000000000 0000037ffffe3a28 0000037ffffe3a20 0000000000000000 0000000000000000 0000000000000000 0000000000f4acf6 00000000001044f0 0000037ffffe3cb0 0000000000000000 0000000000000000 00000000002b55bc 0000037ffffe3bb8 Krnl Code: 00000000002b55b0: c02000840051 larl %r2,0000000001335652 00000000002b55b6: c0e5fff512d1 brasl %r14,0000000000157b58 #00000000002b55bc: af000000 mc 0,0 >00000000002b55c0: a7f4ffe7 brc 15,00000000002b558e 00000000002b55c4: 0707 bcr 0,%r7 00000000002b55c6: 0707 bcr 0,%r7 00000000002b55c8: eb6ff0480024 stmg %r6,%r15,72(%r15) 00000000002b55ce: b90400ef lgr %r14,%r15 Call Trace: [<00000000002b55c0>] arch_ftrace_ops_list_func+0x250/0x258 ([<00000000002b55bc>] arch_ftrace_ops_list_func+0x24c/0x258) [<0000000000f5f0fc>] ftrace_common+0x1c/0x20 [<00000000001044f6>] arch_cpu_idle+0x6/0x28 [<0000000000f4acf6>] default_idle_call+0x76/0x128 [<00000000001cc374>] do_idle+0xf4/0x1b0 [<00000000001cc6ce>] cpu_startup_entry+0x36/0x40 [<0000000000119d00>] smp_start_secondary+0x140/0x150 [<0000000000f5d2ae>] restart_int_handler+0x6e/0x90 Mark arch_cpu_idle() noinstr like all other architectures with CONFIG_ARCH_WANTS_NO_INSTR (should) have it to fix this. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* s390/idle: move idle time accounting to account_idle_time_irq()Heiko Carstens2023-02-091-10/+11
| | | | | | | | | | There is no reason to do idle time accounting in arch_cpu_idle(). Do idle time accounting in account_idle_time_irq(), where it belongs to. The accounted values don't change between account_idle_time_irq() and arch_cpu_idle(); so the result is the same. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* Merge branch 'cmpxchg_user_key' into featuresHeiko Carstens2023-02-094-45/+285
|\ | | | | | | Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * s390/uaccess: avoid __ashlti3() callHeiko Carstens2023-01-041-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | __cmpxchg_user_key() uses 128 bit types which, depending on compiler and config options, may lead to an __ashlti3() library call. Get rid of that by simply casting the 128 bit values to 32 bit values. Reported-by: kernel test robot <lkp@intel.com> Suggested-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> Fixes: 51098f0eb22e ("s390/cmpxchg: make loop condition for 1,2 byte cases precise") Link: https://lore.kernel.org/all/4b96b112d5415d08a81d30657feec2c8c3000f7c.camel@linux.ibm.com/ Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * s390/uaccess: limit number of retries for cmpxchg_user_key()Janis Schoetterl-Glausch2022-11-221-8/+25
| | | | | | | | | | | | | | | | | | | | | | cmpxchg_user_key() for byte and short values is implemented via a one word cmpxchg loop. Give up trying to perform the cmpxchg if it fails too often because of contention on the cache line. This ensures that the thread cannot become stuck in the kernel. Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> Link: https://lore.kernel.org/r/20221117100745.3253896-1-scgl@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * s390/cmpxchg: make loop condition for 1,2 byte cases preciseJanis Schoetterl-Glausch2022-11-212-62/+78
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The cmpxchg implementation for 1 and 2 bytes consists of a 4 byte cmpxchg loop. Currently, the decision to retry is imprecise, looping if bits outside the target byte(s) change instead of retrying until the target byte(s) differ from the old value. E.g. if an attempt to exchange (prev_left_0 old_bytes prev_right_0) is made and it fails because the word at the address is (prev_left_1 x prev_right_1) where both x != old_bytes and one of the prev_*_1 values differs from the respective prev_*_0 value, the cmpxchg is retried, even if by a semantic equivalent to a normal cmpxchg, the exchange would fail. Instead exit the loop if x != old_bytes and retry otherwise. Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> Link: https://lore.kernel.org/r/20221116144711.3811011-1-scgl@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * s390/uaccess: add cmpxchg_user_key()Heiko Carstens2022-11-211-0/+183
| | | | | | | | | | | | | | | | | | | | | | | | | | Add cmpxchg_user_key() which allows to execute a compare and exchange on a user space address. This allows also to specify a storage key which makes sure that key-controlled protection is considered. This is based on a patch written by Janis Schoetterl-Glausch. Link: https://lore.kernel.org/all/20220930210751.225873-2-scgl@linux.ibm.com Cc: Janis Schoetterl-Glausch <scgl@linux.ibm.com> Link: https://lore.kernel.org/r/Y2J8axs+bcQ2dO/l@osiris Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * s390/extable: add EX_TABLE_UA_LOAD_REGPAIR() macroHeiko Carstens2022-11-212-2/+11
| | | | | | | | | | | | | | | | | | | | | | Add new exception table type which is able to handle register pairs. If an exception is recognized on such an instruction the specified register pair will be zeroed, and the specified error register will be modified so it contains -EFAULT, similar to the existing EX_TABLE_UA_LOAD_REG() macro. Link: https://lore.kernel.org/r/Y2J8RSW2khWLgpPo@osiris Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * s390/cmpxchg: remove digits from input constraintsHeiko Carstens2022-11-211-8/+6
| | | | | | | | | | | | | | | | | | Instead of using a digit for input constraints simply initialize the corresponding output operand in C code and use a "+" constraint modifier. Link: https://lore.kernel.org/r/Y2J8H82B6JhJhrp2@osiris Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * s390/cmpxchg: make variables local to each case labelHeiko Carstens2022-11-211-8/+17
| | | | | | | | | | | | | | | | Make variables local to each case label. This limits the scope of variables and allows to use proper types everywhere. Link: https://lore.kernel.org/r/Y2J7+HqgAZwnfxsh@osiris Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * s390/cmpxchg: use symbolic names for inline assembly operandsHeiko Carstens2022-11-211-34/+42
| | | | | | | | | | | | | | | | Make cmpxchg() inline assemblies more readable by using symbolic names for operands. Link: https://lore.kernel.org/r/Y2J7yzQYt/bjLQXY@osiris Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | Merge branch 'fixes' into featuresHeiko Carstens2023-02-061-1/+1
|\ \ | | | | | | | | | Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| * | s390/decompressor: specify __decompress() buf len to avoid overflowVasily Gorbik2023-01-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Historically calls to __decompress() didn't specify "out_len" parameter on many architectures including s390, expecting that no writes beyond uncompressed kernel image are performed. This has changed since commit 2aa14b1ab2c4 ("zstd: import usptream v1.5.2") which includes zstd library commit 6a7ede3dfccb ("Reduce size of dctx by reutilizing dst buffer (#2751)"). Now zstd decompression code might store literal buffer in the unwritten portion of the destination buffer. Since "out_len" is not set, it is considered to be unlimited and hence free to use for optimization needs. On s390 this might corrupt initrd or ipl report which are often placed right after the decompressor buffer. Luckily the size of uncompressed kernel image is already known to the decompressor, so to avoid the problem simply specify it in the "out_len" parameter. Link: https://github.com/facebook/zstd/commit/6a7ede3dfccb Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com> Link: https://lore.kernel.org/r/patch-1.thread-41c676.git-41c676c2d153.your-ad-here.call-01675030179-ext-9637@work.hours Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/boot: avoid potential amode31 truncationVasily Gorbik2023-02-061-1/+1
| | | | | | | | | | | | | | | | | | | | | Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/boot: move detect_facilities() after cmd line parsingVasily Gorbik2023-02-061-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Facilities setup has to be done after "facilities" command line option parsing, it might set extra or remove existing facilities bits for testing purposes. Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/kasan: avoid mapping KASAN shadow for standby memoryVasily Gorbik2023-02-062-22/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KASAN common code is able to handle memory hotplug and create KASAN shadow memory on a fly. Online memory ranges are available from mem_detect, use this information to avoid mapping KASAN shadow for standby memory. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/boot: avoid page tables memory in kaslrVasily Gorbik2023-02-064-6/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If kernel is build without KASAN support there is a chance that kernel image is going to be positioned by KASLR code to overlap with identity mapping page tables. When kernel is build with KASAN support enabled memory which is potentially going to be used for page tables and KASAN shadow mapping is accounted for in KASLR with the use of kasan_estimate_memory_needs(). Split this function and introduce vmem_estimate_memory_needs() to cover decompressor's vmem identity mapping page tables. Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/mem_detect: add get_mem_detect_online_total()Vasily Gorbik2023-02-061-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | Add a function to get online memory in total. It is supposed to be used in the decompressor as well as during early kernel startup. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/mem_detect: handle online memory limit just onceVasily Gorbik2023-02-067-16/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce mem_detect_truncate() to cut any online memory ranges above established identity mapping size, so that mem_detect users wouldn't have to do it over and over again. Suggested-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/boot: fix mem_detect extended area allocationVasily Gorbik2023-02-064-52/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allocation of mem_detect extended area was not considered neither in commit 9641b8cc733f ("s390/ipl: read IPL report at early boot") nor in commit b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)"). As a result mem_detect extended theoretically may overlap with ipl report or randomized kernel image position. But as mem_detect code will allocate extended area only upon exceeding 255 online regions (which should alternate with offline memory regions) it is not seen in practice. To make sure mem_detect extended area does not overlap with ipl report or randomized kernel position extend usage of "safe_addr". Make initrd handling and mem_detect extended area allocation code move it further right and make KASLR takes in into consideration as well. Fixes: 9641b8cc733f ("s390/ipl: read IPL report at early boot") Fixes: b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/mem_detect: rely on diag260() if sclp_early_get_memsize() failsVasily Gorbik2023-02-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case sclp_early_get_memsize() fails but diag260() succeeds make sure some sane value is returned. This error scenario is highly unlikely, but this change makes system able to boot in such case. Suggested-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/diag: make __diag8c_tmp_amode31 staticHeiko Carstens2023-02-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Get rid of this sparse warning: arch/s390/kernel/diag.c:69:29: warning: symbol '__diag8c_tmp_amode31' was not declared. Should it be static? Fixes: fbaee7464fbb ("s390/tty3270: add support for diag 8c") Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/rethook: add local rethook header fileHeiko Carstens2023-02-063-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compiling the kernel with CONFIG_KPROBES disabled, but CONFIG_RETHOOK enabled, results in this sparse warning: arch/s390/kernel/rethook.c:26:15: warning: no previous prototype for 'arch_rethook_trampoline_callback' [-Wmissing-prototypes] 26 | unsigned long arch_rethook_trampoline_callback(struct pt_regs *regs) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Add a local rethook header file similar to riscv to address this. Reported-by: kernel test robot <lkp@intel.com> Fixes: 1a280f48c0e4 ("s390/kprobes: replace kretprobe with rethook") Link: https://lore.kernel.org/all/202302030102.69dZIuJk-lkp@intel.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/vmem: remove unnecessary KASAN checksVasily Gorbik2023-02-061-12/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kasan shadow memory area has been moved to the end of kernel address space since commit 9a39abb7c9aa ("s390/boot: simplify and fix kernel memory layout setup"), therefore skipping any memory ranges above VMALLOC_START in empty page tables cleanup code already handles KASAN shadow memory intersection case and explicit checks could be removed. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/vmem: fix empty page tables cleanup under KASANVasily Gorbik2023-02-061-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit b9ff81003cf1 ("s390/vmem: cleanup empty page tables") introduced empty page tables cleanup in vmem code, but when the kernel is built with KASAN enabled the code has no effect due to wrong KASAN shadow memory intersection condition, which effectively ignores any memory range below KASAN shadow. Fix intersection condition to make code work as anticipated. Fixes: b9ff81003cf1 ("s390/vmem: cleanup empty page tables") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/kasan: update kasan memory layout noteVasily Gorbik2023-02-061-30/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kasan shadow memory area has been moved to the end of kernel address space since commit 9a39abb7c9aa ("s390/boot: simplify and fix kernel memory layout setup"). Change kasan memory layout note accordingly. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/mem_detect: fix detect_memory() error handlingVasily Gorbik2023-02-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently if for some reason sclp_early_read_info() fails, sclp_early_get_memsize() will not set max_physmem_end and it will stay uninitialized. Any garbage value other than 0 will lead to detect_memory() taking wrong path or returning a garbage value as max_physmem_end. To avoid that simply initialize max_physmem_end. Fixes: 73045a08cf55 ("s390: unify identity mapping limits handling") Reported-by: Alexander Gordeev <agordeev@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/ipl: add loadparm parameter to eckd ipl/reipl dataSven Schnelle2023-02-061-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 87fd22e0ae92 ("s390/ipl: add eckd support") missed to add the loadparm attribute to the new eckd ipl/reipl data. Fixes: 87fd22e0ae92 ("s390/ipl: add eckd support") Cc: <stable@vger.kernel.org> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/ipl: add DEFINE_GENERIC_LOADPARM()Sven Schnelle2023-02-061-71/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the current code each reipl type implements its own pair of loadparm show/store functions. Add a macro to deduplicate the code a bit. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Fixes: 87fd22e0ae92 ("s390/ipl: add eckd support") Cc: <stable@vger.kernel.org> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/mem_detect: do not update output parameters on failureAlexander Gordeev2023-01-311-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Function __get_mem_detect_block() resets start and end output parameters in case of invalid mem_detect array index is provided. That violates the rule of sparing the output on fail path and leads e.g to a below anomaly: for_each_mem_detect_block(i, &start, &end) continue; One would expect start and end contain addresses of the last memory block (if available), but in fact the two will be reset to zeroes. That is not how an iterator is expected to work. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/cio: introduce locking for register/unregister functionsVineeth Vijayan2023-01-311-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unbinding an I/O subchannel with a child-CCW device in disconnected state sometimes causes a kernel-panic. The race condition was seen mostly during testing, when setting all the CHPIDs of a device to offline and at the same time, the unbinding the I/O subchannel driver. The kernel-panic occurs because of double delete, the I/O subchannel driver calls device_del on the CCW device while another device_del invocation for the same device is in-flight. For instance, disabling all the CHPIDs will trigger the ccw_device_remove function, which will call a ccw_device_unregister(), which ends up calling the device_del() which is asynchronous via cdev's todo workqueue. And unbinding the I/O subchannel driver calls io_subchannel_remove() function which calls the ccw_device_unregister() and device_del(). This double delete can be prevented by serializing all CCW device registration/unregistration calls into the driver core. This patch introduces a mutex which will be used for this purpose. Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com> Reported-by: Boris Fiuczynski <fiuczy@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/mm,ptdump: avoid Kasan vs Memcpy Real markers swappingVasily Gorbik2023-01-311-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ---[ Real Memory Copy Area Start ]--- 0x001bfffffffff000-0x001c000000000000 4K PTE I ---[ Kasan Shadow Start ]--- ---[ Real Memory Copy Area End ]--- 0x001c000000000000-0x001c000200000000 8G PMD RW NX ... ---[ Kasan Shadow End ]--- ptdump does a stable sort of markers. Move kasan markers after memcpy real to avoid swapping. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/boot: remove pgtable_populate_endVasily Gorbik2023-01-311-27/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | setup_vmem() already calls populate for all online memory regions. pgtable_populate_end() could be removed. Also rename pgtable_populate_begin() to pgtable_populate_init(). Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/boot: avoid mapping standby memoryVasily Gorbik2023-01-313-9/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit bb1520d581a3 ("s390/mm: start kernel with DAT enabled") doesn't consider online memory holes due to potential memory offlining and erroneously creates pgtables for stand-by memory, which bear RW+X attribute and trigger a warning: RANGE SIZE STATE REMOVABLE BLOCK 0x0000000000000000-0x0000000c3fffffff 49G online yes 0-48 0x0000000c40000000-0x0000000c7fffffff 1G offline 49 0x0000000c80000000-0x0000000fffffffff 14G online yes 50-63 0x0000001000000000-0x00000013ffffffff 16G offline 64-79 s390/mm: Found insecure W+X mapping at address 0xc40000000 WARNING: CPU: 14 PID: 1 at arch/s390/mm/dump_pagetables.c:142 note_page+0x2cc/0x2d8 Map only online memory ranges which fit within identity mapping limit. Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/syscalls: get rid of system call alias functionsHeiko Carstens2023-01-251-66/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bpftrace and friends only consider functions present in /sys/kernel/tracing/available_filter_functions. For system calls there is the s390 specific problem that the system call function itself is present via __se_sys##name() while the system call itself is wired up via an __s390x_sys##name() alias. The required DWARF debug information however is only available for the original function, not the alias, but within available_filter_functions only the functions with __s390x_ prefix are available. Which means the required DWARF debug information cannot be found. While this could be solved via tooling, it is easier to change the s390 specific system call wrapper handling. Therefore get rid of this alias handling and implement system call wrappers like most other architectures are doing. In result the implementation generates the following functions: long __s390x_sys##name(struct pt_regs *regs) static inline long __se_sys##name(...) static inline long __do_sys##name(...) __s390x_sys##name() is the visible system call function which is also wired up in the system call table. Its only parameter is a pt_regs variable. This function calls the corresponding __se_sys##name() function, which has as many parameters like the system call definition. This function in turn performs all zero and sign extensions of all system call parameters, taken from the pt_regs structure, and finally calls __do_sys##name(). __do_sys##name() is the actual inlined system call function implementation. For all 64 bit system calls there is a 31/32 bit system call function __s390_sys##name() generated, which handles all system call parameters correctly as required by compat handling. This function may be wired up within the compat system call table, unless there exists an explicit compat system call function, which is then used instead. Reported-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/syscalls: remove trailing semicolonHeiko Carstens2023-01-251-1/+1
| | | | | | | | | | | | | | | Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/syscalls: move __S390_SYS_STUBx() macroHeiko Carstens2023-01-251-13/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | Move __S390_SYS_STUBx() the end of the CONFIG_COMPAT section, so both variants (compat and non-compat) are close together and can be easily compared. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/syscalls: remove __SC_COMPAT_TYPE defineHeiko Carstens2023-01-251-2/+0
| | | | | | | | | | | | | | | | | | | | | Remove __SC_COMPAT_TYPE define which is an unused leftover. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/syscalls: remove SYSCALL_METADATA() from compat syscallsHeiko Carstens2023-01-251-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SYSCALL_METADATA() is only supposed to be used for non-compat system calls. Otherwise there would be a name clash. This also removes the inconsistency that s390 is the only architecture which uses SYSCALL_METADATA() for compat system calls, and even that only for compat system calls without parameters. Only two such compat system calls exist. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390: discard .interp sectionIlya Leoshkevich2023-01-251-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When debugging vmlinux with QEMU + GDB, the following GDB error may occur: (gdb) c Continuing. Warning: Cannot insert breakpoint -1. Cannot access memory at address 0xffffffffffff95c0 Command aborted. (gdb) The reason is that, when .interp section is present, GDB tries to locate the file specified in it in memory and put a number of breakpoints there (see enable_break() function in gdb/solib-svr4.c). Sometimes GDB finds a bogus location that matches its heuristics, fails to set a breakpoint and stops. This makes further debugging impossible. The .interp section contains misleading information anyway (vmlinux does not need ld.so), so fix by discarding it. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/cpum_cf: simplify PMC_INIT and PMC_RELEASE usageThomas Richter2023-01-251-11/+7
| | | | | | | | | | | | | | | | | | | | | | | | Simplify the use of constants PMC_INIT and PMC_RELEASE. Suggested-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/cpum_cf: merge source files for CPU Measurement counter facilityThomas Richter2023-01-255-260/+208
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With no in-kernel user, the source files can be merged. Move all functions and the variable definitions to file perf_cpum_cf.c This file now contains all the necessary functions and definitions for the CPU Measurement counter facility device driver. The files cpu_mcf.h and perf_cpum_cf_common.c are deleted. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
* | | s390/cpum_cf: remove in-kernel counting facility interfaceThomas Richter2023-01-253-42/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 17bebcc68eee ("s390/cpum_cf: Add minimal in-kernel interface for counter measurements") introduced a small in-kernel interface for CPU Measurement counter facility. There are no users of this interface, therefore remove it. The following functions are removed: kernel_cpumcf_alert(), kernel_cpumcf_begin(), kernel_cpumcf_end(), kernel_cpumcf_avail() there is no need for them anymore. With the removal of function kernel_cpumcf_alert(), also remove member alert in struct cpu_cf_events. Its purpose was to counter measurement alert interrupts for the in-kernel interface. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>