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* powerpc/64s: Fix unrelocated interrupt trampoline address testNicholas Piggin2019-03-011-4/+5
| | | | | | | | | | The recent commit got this test wrong, it declared the assembler symbols the wrong way, and also used the wrong symbol name (xxx_start rather than start_xxx, see asm/head-64.h). Fixes: ccd477028a ("powerpc/64s: Fix HV NMI vs HV interrupt recoverability test") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s: system reset interrupt preserve HSRRsNicholas Piggin2019-02-261-1/+24
| | | | | | | | | | | | Code that uses HSRR registers is not required to clear MSR[RI] by convention, however the system reset NMI itself may use HSRR registers (e.g., to call OPAL) and clobber them. Rather than introduce the requirement to clear RI in order to use HSRRs, have system reset interrupt save and restore HSRRs. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s: Fix HV NMI vs HV interrupt recoverability testNicholas Piggin2019-02-261-0/+66
| | | | | | | | | | | | | | | HV interrupts that use HSRR registers do not enter with MSR[RI] clear, but their entry code is not recoverable vs NMI, due to shared use of HSPRG1 as a scratch register to save r13. This means that a system reset or machine check that hits in HSRR interrupt entry can cause r13 to be silently corrupted. Fix this by marking NMIs non-recoverable if they land in HV interrupt ranges. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/traps: fix recoverability of machine check handling on book3s/32Christophe Leroy2019-02-211-4/+4
| | | | | | | | | | | | Looks like book3s/32 doesn't set RI on machine check, so checking RI before calling die() will always be fatal allthought this is not an issue in most cases. Fixes: b96672dd840f ("powerpc: Machine check interrupt is a non-maskable interrupt") Fixes: daf00ae71dad ("powerpc/traps: restore recoverability of machine_check interrupts") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/traps: Fix the message printed when stack overflowsChristophe Leroy2019-01-301-2/+2
| | | | | | | | | | | | | | | | Today's message is useless: [ 42.253267] Kernel stack overflow in process (ptrval), r1=c65500b0 This patch fixes it: [ 66.905235] Kernel stack overflow in process sh[356], r1=c65560b0 Fixes: ad67b74d2469 ("printk: hash addresses printed with %p") Cc: stable@vger.kernel.org # v4.15+ Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Use task_pid_nr()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s: Add MMU type to __die() outputMichael Ellerman2019-01-151-1/+3
| | | | | | | | | | | | | | | | | | On Power9 machines (64-bit Book3S), we can be running with either the Hash table or Radix tree MMU enabled. So add some text to the __die() output to tell us which is enabled, for the case where all you have is the oops output and no other information. Example output: kernel BUG at drivers/misc/lkdtm/bugs.c:63! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries Modules linked in: kvm vmx_crypto binfmt_misc ip_tables x_tables Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Show PAGE_SIZE in __die() outputMichael Ellerman2019-01-151-1/+2
| | | | | | | | | | | | | | | | The page size the kernel is built with is useful info when debugging a crash, so add it to the output in __die(). Result looks like eg: kernel BUG at drivers/misc/lkdtm/bugs.c:63! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K SMP NR_CPUS=2048 NUMA pSeries Modules linked in: vmx_crypto kvm binfmt_misc ip_tables Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Stop using pr_cont() in __die()Michael Ellerman2019-01-151-18/+8Star
| | | | | | | | | Using pr_cont() risks having our output interleaved with other output from other CPUs. Instead print everything in a single printk() call. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Remove 'type' argument from access_ok() functionLinus Torvalds2019-01-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* powerpc/tm: Print scratch valueBreno Leitao2018-12-211-1/+2
| | | | | | | | | | | | | | | | | | Usually a TM Bad Thing exception is raised due to three different problems. a) touching SPRs in an active transaction; b) using TM instruction with the facility disabled and c) setting a wrong MSR/SRR1 at RFID. The two initial cases are easy to identify by looking at the instructions. The latter case is harder, because the MSR is masked after RFID, so, it is very useful to look at the previous MSR (SRR1) before RFID as also the current and masked MSR. Since MSR is saved at paca just before RFID, this patch prints it if a TM Bad thing happen, helping to understand what is the invalid TM transition that is causing the exception. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge tag 'powerpc-4.20-1' of ↵Linus Torvalds2018-10-261-63/+60Star
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - A large series to rewrite our SLB miss handling, replacing a lot of fairly complicated asm with much fewer lines of C. - Following on from that, we now maintain a cache of SLB entries for each process and preload them on context switch. Leading to a 27% speedup for our context switch benchmark on Power9. - Improvements to our handling of SLB multi-hit errors. We now print more debug information when they occur, and try to continue running by flushing the SLB and reloading, rather than treating them as fatal. - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9). - Add support for physical memory up to 2PB in the linear mapping on 64-bit Book3S. We only support up to 512TB as regular system memory, otherwise the percpu allocator runs out of vmalloc space. - Add stack protector support for 32 and 64-bit, with a per-task canary. - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP. - Support recognising "big cores" on Power9, where two SMT4 cores are presented to us as a single SMT8 core. - A large series to cleanup some of our ioremap handling and PTE flags. - Add a driver for the PAPR SCM (storage class memory) interface, allowing guests to operate on SCM devices (acked by Dan). - Changes to our ftrace code to handle very large kernels, where we need to use a trampoline to get to ftrace_caller(). And many other smaller enhancements and cleanups. Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao, Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann, Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab, Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang" * tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits) Revert "selftests/powerpc: Fix out-of-tree build errors" powerpc/msi: Fix compile error on mpc83xx powerpc: Fix stack protector crashes on CPU hotplug powerpc/traps: restore recoverability of machine_check interrupts powerpc/64/module: REL32 relocation range check powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd selftests/powerpc: Add a test of wild bctr powerpc/mm: Fix page table dump to work on Radix powerpc/mm/radix: Display if mappings are exec or not powerpc/mm/radix: Simplify split mapping logic powerpc/mm/radix: Remove the retry in the split mapping logic powerpc/mm/radix: Fix small page at boundary when splitting powerpc/mm/radix: Fix overuse of small pages in splitting logic powerpc/mm/radix: Fix off-by-one in split mapping logic powerpc/ftrace: Handle large kernel configs powerpc/mm: Fix WARN_ON with THP NUMA migration selftests/powerpc: Fix out-of-tree build errors powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64 powerpc/time: isolate scaled cputime accounting in dedicated functions. ...
| * powerpc/traps: restore recoverability of machine_check interruptsChristophe Leroy2018-10-201-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b96672dd840f ("powerpc: Machine check interrupt is a non- maskable interrupt") added a call to nmi_enter() at the beginning of machine check restart exception handler. Due to that, in_interrupt() always returns true regardless of the state before entering the exception, and die() panics even when the system was not already in interrupt. This patch calls nmi_exit() before calling die() in order to restore the interrupt state we had before calling nmi_enter() Fixes: b96672dd840f ("powerpc: Machine check interrupt is a non-maskable interrupt") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/traps: remove redundant in_interrupt panic in die()Christophe Leroy2018-10-181-2/+0Star
| | | | | | | | | | | | | | | | | | do_exit() already includes a test to panic() is in_interrupt() This patch removes powerpc one which is redundant. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/traps: fix machine check handlers to use pr_cont()Christophe Leroy2018-10-181-39/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When printing the machine check cause, the cause appears on the following line due to bad use of printk without \n: [ 33.663993] Machine check in kernel mode. [ 33.664011] Caused by (from SRR1=9032): [ 33.664036] Data access error at address c90c8000 This patch fixes it by using pr_cont() for the second part: [ 133.258131] Machine check in kernel mode. [ 133.258146] Caused by (from SRR1=9032): Data access error at address c90c8000 Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/64s: consolidate MCE counter increment.Michal Suchanek2018-10-031-3/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The code in machine_check_exception excludes 64s hvmode when incrementing the MCE counter only to call opal_machine_check to increment it specifically for this case. Remove the exclusion and special case. Fixes: a43c1590426c ("powerpc/pseries: Flush SLB contents on SLB MCE errors.") Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/tm: Print 64-bits MSRBreno Leitao2018-10-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | On a kernel TM Bad thing program exception, the Machine State Register (MSR) is not being properly displayed. The exception code dumps a 32-bits value but MSR is a 64 bits register for all platforms that have HTM enabled. This patch dumps the MSR value as a 64-bits value instead of 32 bits. In order to do so, the 'reason' variable could not be used, since it trimmed MSR to 32-bits (int). Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/traps: merge unrecoverable_exception() and nonrecoverable_exception()Christophe Leroy2018-10-031-10/+2Star
| | | | | | | | | | | | | | | | | | | | | | | | PPC32 uses nonrecoverable_exception() while PPC64 uses unrecoverable_exception(). Both functions are doing almost the same thing. This patch removes nonrecoverable_exception() Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/tm: Fix HTM documentationBreno Leitao2018-09-171-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch simply fix part of the documentation on the HTM code. This fixes reference to old fields that were renamed in commit 000ec280e3dd ("powerpc: tm: Rename transct_(*) to ck(\1)_state") It also documents better the flow after commit eb5c3f1c8647 ("powerpc: Always save/restore checkpointed regs during treclaim/trecheckpoint"), where tm_recheckpoint can recheckpoint what is in ck{fp,vr}_state blindly. Signed-off-by: Breno Leitao <leitao@debian.org> Acked-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | signal/powerpc: Simplify _exception_pkey by using force_sig_pkuerrEric W. Biederman2018-09-211-9/+1Star
| | | | | | | | | | | | | | | | Call force_sig_pkuerr directly instead of rolling it by hand in _exception_pkey. Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | signal/powerpc: Specialize _exception_pkey for handling pkey exceptionsEric W. Biederman2018-09-211-5/+5
| | | | | | | | | | | | | | | | | | | | Now that _exception no longer calls _exception_pkey it is no longer necessary to handle any signal with any si_code. All pkey exceptions are SIGSEGV with paired with SEGV_PKUERR. So just handle that case and remove the now unnecessary parameters from _exception_pkey. Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | signal/powerpc: Call force_sig_fault from _exceptionEric W. Biederman2018-09-211-1/+4
| | | | | | | | | | | | | | | | | | | | The callers of _exception don't need the pkey exception logic because they are not processing a pkey exception. So just call exception_common directly and then call force_sig_fault to generate the appropriate siginfo and deliver the appropriate signal. Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | signal/powerpc: Factor the common exception code into exception_commonEric W. Biederman2018-09-211-5/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | It is brittle and wrong to populate si_pkey when there was not a pkey exception. The field does not exist for all si_codes and in some cases another field exists in the same memory location. So factor out the code that all exceptions handlers must run into exception_common, leaving the individual exception handlers to generate the signals themselves. Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | signal: Simplify tracehook_report_syscall_exitEric W. Biederman2018-09-191-5/+2Star
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace user_single_step_siginfo with user_single_step_report that allocates siginfo structure on the stack and sends it. This allows tracehook_report_syscall_exit to become a simple if statement that calls user_single_step_report or ptrace_report_syscall depending on the value of step. Update the default helper function now called user_single_step_report to explicitly set si_code to SI_USER and to set si_uid and si_pid to 0. The default helper has always been doing this (using memset) but it was far from obvious. The powerpc helper can now just call force_sig_fault. The x86 helper can now just call send_sigtrap. Unfortunately the default implementation of user_single_step_report can not use force_sig_fault as it does not use a SIGTRAP si_code. So it has to carefully setup the siginfo and use use force_sig_info. The net result is code that is easier to understand and simpler to maintain. Ref: 85ec7fd9f8e5 ("ptrace: introduce user_single_step_siginfo() helper") Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* powerpc/traps: Avoid rate limit messages from show unhandled signalsMichael Ellerman2018-08-201-7/+6Star
| | | | | | | | | | | | | | | | | | | | In the recent commit to add an explicit ratelimit state when showing unhandled signals, commit 35a52a10c3ac ("powerpc/traps: Use an explicit ratelimit state for show_signal_msg()"), I put the check of show_unhandled_signals and the ratelimit state before the call to unhandled_signal() so as to avoid unnecessarily calling the latter when show_unhandled_signals is false. However that causes us to check the ratelimit state on every call, so if we take a lot of *handled* signals that has the effect of making the ratelimit code print warnings that callbacks have been suppressed when they haven't. So rearrange the code so that we check show_unhandled_signals first, then call unhandled_signal() and finally check the ratelimit state. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
* powerpc/traps: Show instructions on exceptionsMurilo Opsfelder Araujo2018-08-071-0/+3
| | | | | | | | | | | | | | | | | | Call show_user_instructions() in arch/powerpc/kernel/traps.c to dump instructions at faulty location, useful to debugging. Before this patch, an unhandled signal message looked like: pandafault[10524]: segfault (11) at 100007d0 nip 1000061c lr 7fffbd295100 code 2 in pandafault[10000000+10000] After this patch, it looks like: pandafault[10524]: segfault (11) at 100007d0 nip 1000061c lr 7fffbd295100 code 2 in pandafault[10000000+10000] pandafault[10524]: code: 4bfffeec 4bfffee8 3c401002 38427f00 fbe1fff8 f821ffc1 7c3f0b78 3d22fffe pandafault[10524]: code: 392988d0 f93f0020 e93f0020 39400048 <99490000> 39200000 7d234b78 383f0040 Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/traps: Print VMA for unhandled signalsMurilo Opsfelder Araujo2018-08-071-2/+19
| | | | | | | | | | | | | | | | This adds VMA address in the message printed for unhandled signals, similarly to what other architectures, like x86, print. Before this patch, a page fault looked like: pandafault[61470]: unhandled signal 11 at 100007d0 nip 1000061c lr 7fff8d185100 code 2 After this patch, a page fault looks like: pandafault[6303]: segfault 11 at 100007d0 nip 1000061c lr 7fff93c55100 code 2 in pandafault[10000000+10000] Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/traps: Use %lx format in show_signal_msg()Murilo Opsfelder Araujo2018-08-071-8/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | Use %lx format to print registers. This avoids having two different formats and avoids checking for MSR_64BIT, improving readability of the function. Even though we could have used %px, which is functionally equivalent to %lx as per Documentation/core-api/printk-formats.rst, it is not semantically correct because the data printed are not pointers. And using %px requires casting data to (void *). Besides that, %lx matches the format used in show_regs(). Before this patch: pandafault[4808]: unhandled signal 11 at 0000000010000718 nip 0000000010000574 lr 00007fff935e7a6c code 2 After this patch: pandafault[4732]: unhandled signal 11 at 10000718 nip 10000574 lr 7fff86697a6c code 2 Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/traps: Use an explicit ratelimit state for show_signal_msg()Murilo Opsfelder Araujo2018-08-071-5/+16
| | | | | | | | | | | Replace printk_ratelimited() by printk() and a default rate limit burst to limit displaying unhandled signals messages. This will allow us to call print_vma_addr() in a future patch, which does not work with printk_ratelimited(). Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/traps: Print unhandled signals in a separate functionMurilo Opsfelder Araujo2018-08-071-10/+16
| | | | | | | | Isolate the logic of printing unhandled signals out of _exception_pkey(). No functional change, only code rearrangement. Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* signal/powerpc: Replace TRAP_FIXME with TRAP_UNKEric W. Biederman2018-04-251-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using an si_code of 0 that aliases with SI_USER is clearly the wrong thing todo, and causes problems in interesting ways. For use in unknown_exception the recently defined TRAP_UNK semantically is a perfect fit. For use in RunModeException it looks like something more specific than TRAP_UNK could be used. No one has bothered to find a better fit than the broken si_code of 0 in all of these years and I don't see an obvious better fit so TRAP_UNK is switching RunModeException to return TRAP_UNK is clearly an improvement. Recent history suggests no actually cares about crazy corner cases of the kernel behavior like this so I don't expect any regressions from changing this. However if something does happen this change is easy to revert. Though I wonder if SIGKILL might not be a better fit. Cc: Paul Mackerras <paulus@samba.org> Cc: Kumar Gala <kumar.gala@freescale.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: linuxppc-dev@lists.ozlabs.org Fixes: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx") Fixes: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* signal/powerpc: Replace FPE_FIXME with FPE_FLTUNKEric W. Biederman2018-04-251-3/+3
| | | | | | | | | | | | | | | | | | Using an si_code of 0 that aliases with SI_USER is clearly the wrong thing todo, and causes problems in interesting ways. The newly defined FPE_FLTUNK semantically appears to fit the bill so use it instead. Cc: Paul Mackerras <paulus@samba.org> Cc: Kumar Gala <kumar.gala@freescale.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: linuxppc-dev@lists.ozlabs.org Fixes: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx") Fixes: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* signal: Ensure every siginfo we send has all bits initializedEric W. Biederman2018-04-251-2/+1Star
| | | | | | | | | | | | | | | | | | | | | | | Call clear_siginfo to ensure every stack allocated siginfo is properly initialized before being passed to the signal sending functions. Note: It is not safe to depend on C initializers to initialize struct siginfo on the stack because C is allowed to skip holes when initializing a structure. The initialization of struct siginfo in tracehook_report_syscall_exit was moved from the helper user_single_step_siginfo into tracehook_report_syscall_exit itself, to make it clear that the local variable siginfo gets fully initialized. In a few cases the scope of struct siginfo has been reduced to make it clear that siginfo siginfo is not used on other paths in the function in which it is declared. Instances of using memset to initialize siginfo have been replaced with calls clear_siginfo for clarity. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* powerpc/fscr: Enable interrupts earlier before calling get_user()Anshuman Khandual2018-04-101-15/+17
| | | | | | | | | | | | | | | | | The function get_user() can sleep while trying to fetch instruction from user address space and causes the following warning from the scheduler. BUG: sleeping function called from invalid context Though interrupts get enabled back but it happens bit later after get_user() is called. This change moves enabling these interrupts earlier covering the function get_user(). While at this, lets check for kernel mode and crash as this interrupt should not have been triggered from the kernel context. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Clear branch trap (MSR.BE) before delivering SIGTRAPMatt Evans2018-04-011-1/+3
| | | | | | | | | | | | | | | | | | When using SIG_DBG_BRANCH_TRACING, MSR.BE is left enabled in the user context when single_step_exception() prepares the SIGTRAP delivery. The resulting branch-trap-within-the-SIGTRAP-handler isn't healthy. Commit 2538c2d08f46141550a1e68819efa8fe31c6e3dc broke this, by replacing an MSR mask operation of ~(MSR_SE | MSR_BE) with a call to clear_single_step() which only clears MSR_SE. This patch adds a new helper, clear_br_trace(), which clears the debug trap before invoking the signal handler. This helper is a NOP for BookE as SIG_DBG_BRANCH_TRACING isn't supported on BookE. Signed-off-by: Matt Evans <matt@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/64s: sreset panic if there is no debugger or crash dump handlersNicholas Piggin2018-03-311-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | system_reset_exception does most of its own crash handling now, invoking the debugger or crash dumps if they are registered. If not, then it goes through to die() to print stack traces, and then is supposed to panic (according to comments). However after die() prints oopses, it does its own handling which doesn't allow system_reset_exception to panic (e.g., it may just kill the current process). This patch causes sreset exceptions to return from die after it prints messages but before acting. This also stops die from invoking the debugger on 0x100 crashes. system_reset_exception similarly calls the debugger. It had been thought this was harmless (because if the debugger was disabled, neither call would fire, and if it was enabled the first call would return). However in some cases like xmon 'X' command, the debugger returns 0, which currently causes it to be entered again (first in system_reset_exception, then in die), which is confusing. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: Add support for handling > 512TB address in SLB missAneesh Kumar K.V2018-03-301-12/+0Star
| | | | | | | | | | | | | | For addresses above 512TB we allocate additional mmu contexts. To make it all easy, addresses above 512TB are handled with IR/DR=1 and with stack frame setup. The mmu_context_t is also updated to track the new extended_ids. To support upto 4PB we need a total 8 contexts. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [mpe: Minor formatting tweaks and comment wording, switch BUG to WARN in get_ea_context().] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge tag 'powerpc-4.16-1' of ↵Linus Torvalds2018-02-021-5/+46
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights: - Enable support for memory protection keys aka "pkeys" on Power7/8/9 when using the hash table MMU. - Extend our interrupt soft masking to support masking PMU interrupts as well as "normal" interrupts, and then use that to implement local_t for a ~4x speedup vs the current atomics-based implementation. - A new driver "ocxl" for "Open Coherent Accelerator Processor Interface (OpenCAPI)" devices. - Support for new device tree properties on PowerVM to describe hotpluggable memory and devices. - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit VDSO. - Freescale updates from Scott: fixes for CPM GPIO and an FSL PCI erratum workaround, plus a minor cleanup patch. As well as quite a lot of other changes all over the place, and small fixes and cleanups as always. Thanks to: Alan Modra, Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual, Anton Blanchard, Arnd Bergmann, Balbir Singh, Benjamin Herrenschmidt, Bhaktipriya Shridhar, Bryant G. Ly, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Cyril Bur, David Gibson, Desnes A. Nunes do Rosario, Dmitry Torokhov, Frederic Barrat, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo A. R. Silva, Gustavo Romero, Ivan Mikhaylov, Joakim Tjernlund, Joe Perches, Josh Poimboeuf, Juan J. Alvarez, Julia Cartwright, Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud, Ram Pai, Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee, Simon Guo, Stewart Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann, Vaibhav Jain, Vasyl Gomonovych" * tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (199 commits) powerpc/mm/radix: Fix build error when RADIX_MMU=n macintosh/ams-input: Use true and false for boolean values macintosh: change some data types from int to bool powerpc/watchdog: Print the NIP in soft_nmi_interrupt() powerpc/watchdog: regs can't be null in soft_nmi_interrupt() powerpc/watchdog: Tweak watchdog printks powerpc/cell: Remove axonram driver rtc-opal: Fix handling of firmware error codes, prevent busy loops powerpc/mpc52xx_gpt: make use of raw_spinlock variants macintosh/adb: Properly mark continued kernel messages powerpc/pseries: Fix cpu hotplug crash with memoryless nodes powerpc/numa: Ensure nodes initialized for hotplug powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes powerpc/kernel: Block interrupts when updating TIDR powerpc/powernv/idoa: Remove unnecessary pcidev from pci_dn powerpc/mm/nohash: do not flush the entire mm when range is a single page powerpc/pseries: Add Initialization of VF Bars powerpc/pseries/pci: Associate PEs to VFs in configure SR-IOV powerpc/eeh: Add EEH notify resume sysfs powerpc/eeh: Add EEH operations to notify resume ...
| * powerpc/pseries, ps3: panic flush kernel messages before halting systemNicholas Piggin2018-01-221-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Platforms with a panic handler that halts the system can have problems getting kernel messages out, because the panic notifiers are called before kernel/panic.c does its flushing of printk buffers an console etc. This was attempted to be solved with commit a3b2cb30f252 ("powerpc: Do not call ppc_md.panic in fadump panic notifier"), but that wasn't the right approach and caused other problems, and was reverted by commit ab9dbf771ff9. Instead, the powernv shutdown paths have already had a similar problem, fixed by taking the message flushing sequence from kernel/panic.c. That's a little bit ugly, but while we have the code duplicated, it will work for this case as well. So have ppc panic handlers do the same flushing before they terminate. Without this patch, a qemu pseries_le_defconfig guest stops silently when issued the nmi command when xmon is off and no crash dumpers enabled. Afterwards, an oops is printed by each CPU as expected. Fixes: ab9dbf771ff9 ("Revert "powerpc: Do not call ppc_md.panic in fadump panic notifier"") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc: Use octal numbers for file permissionsRussell Currey2018-01-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Symbolic macros are unintuitive and hard to read, whereas octal constants are much easier to interpret. Replace macros for the basic permission flags (user/group/other read/write/execute) with numeric constants instead, across the whole powerpc tree. Introducing a significant number of changes across the tree for no runtime benefit isn't exactly desirable, but so long as these macros are still used in the tree people will keep sending patches that add them. Not only are they hard to parse at a glance, there are multiple ways of coming to the same value (as you can see with 0444 and 0644 in this patch) which hurts readability. Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/ptrace: Add memory protection key regsetThiago Jung Bauermann2018-01-201-0/+7
| | | | | | | | | | | | | | | | | | The AMR/IAMR/UAMOR are part of the program context. Allow it to be accessed via ptrace and through core files. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc: Deliver SEGV signal on pkey violationRam Pai2018-01-201-1/+11
| | | | | | | | | | | | | | | | | | The value of the pkey, whose protection got violated, is made available in si_pkey field of the siginfo structure. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc: System reset avoid interleaving oops using die synchronisationNicholas Piggin2018-01-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The die() oops path contains a serializing lock to prevent oops messages from being interleaved. In the case of a system reset initiated oops (e.g., qemu nmi command), __die was being called which lacks that synchronisation and oops reports could be interleaved across CPUs. A recent patch 4388c9b3a6ee7 ("powerpc: Do not send system reset request through the oops path") changed this to __die to avoid the debugger() call, but there is no real harm to calling it twice if the first time fell through. So go back to using die() here. This was observed to fix the problem. Fixes: 4388c9b3a6ee7 ("powerpc: Do not send system reset request through the oops path") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc: Use the TRAP macro whenever comparing a trap numberBenjamin Herrenschmidt2018-01-161-1/+1
| | | | | | | | | | | | | | | | | | | | Trap numbers can have extra bits at the bottom that need to be filtered out. There are a few cases where we don't do that. It's possible that we got lucky but better safe than sorry. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | signal/powerpc: Remove unnecessary signal_code parameter of do_send_trapEric W. Biederman2018-01-231-6/+6
| | | | | | | | | | | | signal_code is always TRAP_HWBKPT Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | signal/powerpc: Document conflicts with SI_USER and SIGFPE and SIGTRAPEric W. Biederman2018-01-121-5/+5
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Setting si_code to 0 results in a userspace seeing an si_code of 0. This is the same si_code as SI_USER. Posix and common sense requires that SI_USER not be a signal specific si_code. As such this use of 0 for the si_code is a pretty horribly broken ABI. Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a value of __SI_KILL and now sees a value of SIL_KILL with the result that uid and pid fields are copied and which might copying the si_addr field by accident but certainly not by design. Making this a very flakey implementation. Utilizing FPE_FIXME and TRAP_FIXME, siginfo_layout() will now return SIL_FAULT and the appropriate fields will be reliably copied. Possible ABI fixes includee: - Send the signal without siginfo - Don't generate a signal - Possibly assign and use an appropriate si_code - Don't handle cases which can't happen Cc: Paul Mackerras <paulus@samba.org> Cc: Kumar Gala <kumar.gala@freescale.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: linuxppc-dev@lists.ozlabs.org Ref: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx") Ref: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.") History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* powerpc: Remove facility loadups on transactional {fp, vec, vsx} unavailableCyril Bur2017-11-061-30/+0Star
| | | | | | | | | | | | | After handling a transactional FP, Altivec or VSX unavailable exception. The return to userspace code will detect that the TIF_RESTORE_TM bit is set and call restore_tm_state(). restore_tm_state() will call restore_math() to ensure that the correct facilities are loaded. This means that all the loadup code in {fp,altivec,vsx}_unavailable_tm() is doing pointless work and can simply be removed. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Always save/restore checkpointed regs during treclaim/trecheckpointCyril Bur2017-11-061-20/+6Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Lazy save and restore of FP/Altivec means that a userspace process can be sent to userspace with FP or Altivec disabled and loaded only as required (by way of an FP/Altivec unavailable exception). Transactional Memory complicates this situation as a transaction could be started without FP/Altivec being loaded up. This causes the hardware to checkpoint incorrect registers. Handling FP/Altivec unavailable exceptions while a thread is transactional requires a reclaim and recheckpoint to ensure the CPU has correct state for both sets of registers. tm_reclaim() has optimisations to not always save the FP/Altivec registers to the checkpointed save area. This was originally done because the caller might have information that the checkpointed registers aren't valid due to lazy save and restore. We've also been a little vague as to how tm_reclaim() leaves the FP/Altivec state since it doesn't necessarily always save it to the thread struct. This has lead to an (incorrect) assumption that it leaves the checkpointed state on the CPU. tm_recheckpoint() has similar optimisations in reverse. It may not always reload the checkpointed FP/Altivec registers from the thread struct before the trecheckpoint. It is therefore quite unclear where it expects to get the state from. This didn't help with the assumption made about tm_reclaim(). These optimisations sit in what is by definition a slow path. If a process has to go through a reclaim/recheckpoint then its transaction will be doomed on returning to userspace. This mean that the process will be unable to complete its transaction and be forced to its failure handler. This is already an out if line case for userspace. Furthermore, the cost of copying 64 times 128 bits from registers isn't very long[0] (at all) on modern processors. As such it appears these optimisations have only served to increase code complexity and are unlikely to have had a measurable performance impact. Our transactional memory handling has been riddled with bugs. A cause of this has been difficulty in following the code flow, code complexity has not been our friend here. It makes sense to remove these optimisations in favour of a (hopefully) more stable implementation. This patch does mean that some times the assembly will needlessly save 'junk' registers which will subsequently get overwritten with the correct value by the C code which calls the assembly function. This small inefficiency is far outweighed by the reduction in complexity for general TM code, context switching paths, and transactional facility unavailable exception handler. 0: I tried to measure it once for other work and found that it was hiding in the noise of everything else I was working with. I find it exceedingly likely this will be the case here. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Force reload for recheckpoint during tm {fp, vec, vsx} unavailable ↵Cyril Bur2017-11-061-5/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | exception Lazy save and restore of FP/Altivec means that a userspace process can be sent to userspace with FP or Altivec disabled and loaded only as required (by way of an FP/Altivec unavailable exception). Transactional Memory complicates this situation as a transaction could be started without FP/Altivec being loaded up. This causes the hardware to checkpoint incorrect registers. Handling FP/Altivec unavailable exceptions while a thread is transactional requires a reclaim and recheckpoint to ensure the CPU has correct state for both sets of registers. tm_reclaim() has optimisations to not always save the FP/Altivec registers to the checkpointed save area. This was originally done because the caller might have information that the checkpointed registers aren't valid due to lazy save and restore. We've also been a little vague as to how tm_reclaim() leaves the FP/Altivec state since it doesn't necessarily always save it to the thread struct. This has lead to an (incorrect) assumption that it leaves the checkpointed state on the CPU. tm_recheckpoint() has similar optimisations in reverse. It may not always reload the checkpointed FP/Altivec registers from the thread struct before the trecheckpoint. It is therefore quite unclear where it expects to get the state from. This didn't help with the assumption made about tm_reclaim(). This patch is a minimal fix for ease of backporting. A more correct fix which removes the msr parameter to tm_reclaim() and tm_recheckpoint() altogether has been upstreamed to apply on top of this patch. Fixes: dc3106690b20 ("powerpc: tm: Always use fp_state and vr_state to store live registers") Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Don't enable FP/Altivec if not checkpointedCyril Bur2017-11-061-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Lazy save and restore of FP/Altivec means that a userspace process can be sent to userspace with FP or Altivec disabled and loaded only as required (by way of an FP/Altivec unavailable exception). Transactional Memory complicates this situation as a transaction could be started without FP/Altivec being loaded up. This causes the hardware to checkpoint incorrect registers. Handling FP/Altivec unavailable exceptions while a thread is transactional requires a reclaim and recheckpoint to ensure the CPU has correct state for both sets of registers. Lazy save and restore of FP/Altivec cannot be done if a process is transactional. If a facility was enabled it must remain enabled whenever a thread is transactional. Commit dc16b553c949 ("powerpc: Always restore FPU/VEC/VSX if hardware transactional memory in use") ensures that the facilities are always enabled if a thread is transactional. A bug in the introduced code may cause it to inadvertently enable a facility that was (and should remain) disabled. The problem with this extraneous enablement is that the registers for the erroneously enabled facility have not been correctly recheckpointed - the recheckpointing code assumed the facility would remain disabled. Further compounding the issue, the transactional {fp,altivec,vsx} unavailable code has been incorrectly using the MSR to enable facilities. The presence of the {FP,VEC,VSX} bit in the regs->msr simply means if the registers are live on the CPU, not if the kernel should load them before returning to userspace. This has worked due to the bug mentioned above. This causes transactional threads which return to their failure handler to observe incorrect checkpointed registers. Perhaps an example will help illustrate the problem: A userspace process is running and uses both FP and Altivec registers. This process then continues to run for some time without touching either sets of registers. The kernel subsequently disables the facilities as part of lazy save and restore. The userspace process then performs a tbegin and the CPU checkpoints 'junk' FP and Altivec registers. The process then performs a floating point instruction triggering a fp unavailable exception in the kernel. The kernel then loads the FP registers - and only the FP registers. Since the thread is transactional it must perform a reclaim and recheckpoint to ensure both the checkpointed registers and the transactional registers are correct. It then (correctly) enables MSR[FP] for the process. Later (on exception exist) the kernel also (inadvertently) enables MSR[VEC]. The process is then returned to userspace. Since the act of loading the FP registers doomed the transaction we know CPU will fail the transaction, restore its checkpointed registers, and return the process to its failure handler. The problem is that we're now running with Altivec enabled and the 'junk' checkpointed registers are restored. The kernel had only recheckpointed FP. This patch solves this by only activating FP/Altivec if userspace was using them when it entered the kernel and not simply if the process is transactional. Fixes: dc16b553c949 ("powerpc: Always restore FPU/VEC/VSX if hardware transactional memory in use") Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/tm: Don't check for WARN in TM Bad Thing handlingMichael Ellerman2017-11-061-7/+2Star
| | | | | | | | | | | | | | | | | | | | | Currently when we take a TM Bad Thing program check exception, we search the bug table to see if the program check was generated by a WARN/WARN_ON etc. That makes no sense, the WARN macros use trap instructions, which should never generate a TM Bad Thing exception. If they ever did that would be a bug and we should oops. We do have some hand-coded bugs in tm.S, using EMIT_BUG_ENTRY, but those are all BUGs not WARNs, and they all use trap instructions anyway. Almost certainly this check was incorrectly copied from the REASON_TRAP handling in the same function. Remove it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-By: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-22 00:38:32 +0200