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2017-09-21powerpc/eeh: Create PHB PEs after EEH is initializedBenjamin Herrenschmidt2-18/+4
Otherwise we end up not yet having computed the right diag data size on powernv where EEH initialization is delayed, thus causing memory corruption later on when calling OPAL. Fixes: 5cb1f8fdddb7 ("powerpc/powernv/pci: Dynamically allocate PHB diag data") Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-20powerpc/kprobes: Update optprobes to use emulate_update_regs()Naveen N. Rao1-1/+3
Optprobes depended on an updated regs->nip from analyse_instr() to identify the location to branch back from the optprobes trampoline. However, since commit 3cdfcbfd32b9d ("powerpc: Change analyse_instr so it doesn't modify *regs"), analyse_instr() doesn't update the registers anymore. Due to this, we end up branching back from the optprobes trampoline to the same branch into the trampoline resulting in a loop. Fix this by calling out to emulate_update_regs() before using the nip. Additionally, explicitly compare the return value from analyse_instr() to 1, rather than just checking for !0 so as to guard against any future changes to analyse_instr() that may result in -1 being returned in more scenarios. Fixes: 3cdfcbfd32b9d ("powerpc: Change analyse_instr so it doesn't modify *regs") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-20Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into fixesMichael Ellerman1-2/+10
Merge one commit from Scott which I missed while away.
2017-09-20powerpc/tm: Flush TM only if CPU has TM featureGustavo Romero1-1/+1
Commit cd63f3c ("powerpc/tm: Fix saving of TM SPRs in core dump") added code to access TM SPRs in flush_tmregs_to_thread(). However flush_tmregs_to_thread() does not check if TM feature is available on CPU before trying to access TM SPRs in order to copy live state to thread structures. flush_tmregs_to_thread() is indeed guarded by CONFIG_PPC_TRANSACTIONAL_MEM but it might be the case that kernel was compiled with CONFIG_PPC_TRANSACTIONAL_MEM enabled and ran on a CPU without TM feature available, thus rendering the execution of TM instructions that are treated by the CPU as illegal instructions. The fix is just to add proper checking in flush_tmregs_to_thread() if CPU has the TM feature before accessing any TM-specific resource, returning immediately if TM is no available on the CPU. Adding that checking in flush_tmregs_to_thread() instead of in places where it is called, like in vsr_get() and vsr_set(), is better because avoids the same problem cropping up elsewhere. Cc: stable@vger.kernel.org # v4.13+ Fixes: cd63f3c ("powerpc/tm: Fix saving of TM SPRs in core dump") Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com> Reviewed-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-15Merge tag 'powerpc-4.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds1-1/+1
Pull powerpc fix from Michael Ellerman: "Just one fix, for the handling of alignment interrupts on dcbz instructions. Thanks to Paul Mackerras, Christian Zigotzky, Michal Sojka" * tag 'powerpc-4.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc: Fix handling of alignment interrupt on dcbz instruction
2017-09-15powerpc: Fix handling of alignment interrupt on dcbz instructionPaul Mackerras1-1/+1
This fixes the emulation of the dcbz instruction in the alignment interrupt handler. The error was that we were comparing just the instruction type field of op.type rather than the whole thing, and therefore the comparison "type != CACHEOP + DCBZ" was always true. Fixes: 31bfdb036f12 ("powerpc: Use instruction emulation infrastructure to handle alignment faults") Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Tested-by: Michal Sojka <sojkam1@fel.cvut.cz> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-13mm: treewide: remove GFP_TEMPORARY allocation flagMichal Hocko1-2/+2
GFP_TEMPORARY was introduced by commit e12ba74d8ff3 ("Group short-lived and reclaimable kernel allocations") along with __GFP_RECLAIMABLE. It's primary motivation was to allow users to tell that an allocation is short lived and so the allocator can try to place such allocations close together and prevent long term fragmentation. As much as this sounds like a reasonable semantic it becomes much less clear when to use the highlevel GFP_TEMPORARY allocation flag. How long is temporary? Can the context holding that memory sleep? Can it take locks? It seems there is no good answer for those questions. The current implementation of GFP_TEMPORARY is basically GFP_KERNEL | __GFP_RECLAIMABLE which in itself is tricky because basically none of the existing caller provide a way to reclaim the allocated memory. So this is rather misleading and hard to evaluate for any benefits. I have checked some random users and none of them has added the flag with a specific justification. I suspect most of them just copied from other existing users and others just thought it might be a good idea to use without any measuring. This suggests that GFP_TEMPORARY just motivates for cargo cult usage without any reasoning. I believe that our gfp flags are quite complex already and especially those with highlevel semantic should be clearly defined to prevent from confusion and abuse. Therefore I propose dropping GFP_TEMPORARY and replace all existing users to simply use GFP_KERNEL. Please note that SLAB users with shrinkers will still get __GFP_RECLAIMABLE heuristic and so they will be placed properly for memory fragmentation prevention. I can see reasons we might want some gfp flag to reflect shorterm allocations but I propose starting from a clear semantic definition and only then add users with proper justification. This was been brought up before LSF this year by Matthew [1] and it turned out that GFP_TEMPORARY really doesn't have a clear semantic. It seems to be a heuristic without any measured advantage for most (if not all) its current users. The follow up discussion has revealed that opinions on what might be temporary allocation differ a lot between developers. So rather than trying to tweak existing users into a semantic which they haven't expected I propose to simply remove the flag and start from scratch if we really need a semantic for short term allocations. [1] http://lkml.kernel.org/r/20170118054945.GD18349@bombadil.infradead.org [akpm@linux-foundation.org: fix typo] [akpm@linux-foundation.org: coding-style fixes] [sfr@canb.auug.org.au: drm/i915: fix up] Link: http://lkml.kernel.org/r/20170816144703.378d4f4d@canb.auug.org.au Link: http://lkml.kernel.org/r/20170728091904.14627-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Matthew Wilcox <willy@infradead.org> Cc: Neil Brown <neilb@suse.de> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-11Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespaceLinus Torvalds1-11/+9
Pull namespace updates from Eric Biederman: "Life has been busy and I have not gotten half as much done this round as I would have liked. I delayed it so that a minor conflict resolution with the mips tree could spend a little time in linux-next before I sent this pull request. This includes two long delayed user namespace changes from Kirill Tkhai. It also includes a very useful change from Serge Hallyn that allows the security capability attribute to be used inside of user namespaces. The practical effect of this is people can now untar tarballs and install rpms in user namespaces. It had been suggested to generalize this and encode some of the namespace information information in the xattr name. Upon close inspection that makes the things that should be hard easy and the things that should be easy more expensive. Then there is my bugfix/cleanup for signal injection that removes the magic encoding of the siginfo union member from the kernel internal si_code. The mips folks reported the case where I had used FPE_FIXME me is impossible so I have remove FPE_FIXME from mips, while at the same time including a return statement in that case to keep gcc from complaining about unitialized variables. I almost finished the work to get make copy_siginfo_to_user a trivial copy to user. The code is available at: git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git neuter-copy_siginfo_to_user-v3 But I did not have time/energy to get the code posted and reviewed before the merge window opened. I was able to see that the security excuse for just copying fields that we know are initialized doesn't work in practice there are buggy initializations that don't initialize the proper fields in siginfo. So we still sometimes copy unitialized data to userspace" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: Introduce v3 namespaced file capabilities mips/signal: In force_fcr31_sig return in the impossible case signal: Remove kernel interal si_code magic fcntl: Don't use ambiguous SIG_POLL si_codes prctl: Allow local CAP_SYS_ADMIN changing exe_file security: Use user_namespace::level to avoid redundant iterations in cap_capable() userns,pidns: Verify the userns for new pid namespaces signal/testing: Don't look for __SI_FAULT in userspace signal/mips: Document a conflict with SI_USER with SIGFPE signal/sparc: Document a conflict with SI_USER with SIGFPE signal/ia64: Document a conflict with SI_USER with SIGFPE signal/alpha: Document a conflict with SI_USER for SIGTRAP
2017-09-08treewide: make "nr_cpu_ids" unsignedAlexey Dobriyan2-2/+2
First, number of CPUs can't be negative number. Second, different signnnedness leads to suboptimal code in the following cases: 1) kmalloc(nr_cpu_ids * sizeof(X)); "int" has to be sign extended to size_t. 2) while (loff_t *pos < nr_cpu_ids) MOVSXD is 1 byte longed than the same MOV. Other cases exist as well. Basically compiler is told that nr_cpu_ids can't be negative which can't be deduced if it is "int". Code savings on allyesconfig kernel: -3KB add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370) function old new delta coretemp_cpu_online 450 512 +62 rcu_init_one 1234 1272 +38 pci_device_probe 374 399 +25 ... pgdat_reclaimable_pages 628 556 -72 select_fallback_rq 446 369 -77 task_numa_find_cpu 1923 1807 -116 Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-02powerpc/xive: add XIVE Exploitation Mode to CASCédric Le Goater1-1/+33
On POWER9, the Client Architecture Support (CAS) negotiation process determines whether the guest operates in XIVE Legacy compatibility or in XIVE exploitation mode. Now that we have initial guest support for the XIVE interrupt controller, let's inform the hypervisor what we can do. The platform advertises the XIVE Exploitation Mode support using the property "ibm,arch-vec-5-platform-support-vec-5", byte 23 bits 0-1 : - 0b00 XIVE legacy mode Only - 0b01 XIVE exploitation mode Only - 0b10 XIVE legacy or exploitation mode The OS asks for XIVE Exploitation Mode support using the property "ibm,architecture-vec-5", byte 23 bits 0-1: - 0b00 XIVE legacy mode Only - 0b01 XIVE exploitation mode Only Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-01powerpc/iommu: Use permission-specific DEVICE_ATTR variantsJulia Lawall1-2/+1
Use DEVICE_ATTR_RW for read-write attributes. This simplifies the source code, improves readbility, and reduces the chance of inconsistencies. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-01powerpc/eeh: Delete an error out of memory message at init timeMarkus Elfring1-4/+1
Omit an extra message for a memory allocation failure in eeh_dev_init(). This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> [mpe: Do not drop the message that can happen at runtime and lead to an event not being handled] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-01powerpc/32: remove a NOP from memset()Christophe Leroy1-1/+6
memset() is patched after initialisation to activate the optimised part which uses cache instructions. Today we have a 'b 2f' to skip the optimised patch, which then gets replaced by a NOP, implying a useless cycle consumption. As we have a 'bne 2f' just before, we could use that instruction for the live patching, hence removing the need to have a dedicated 'b 2f' to be replaced by a NOP. This patch changes the 'bne 2f' by a 'b 2f'. During init, that 'b 2f' is then replaced by 'bne 2f' Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-01powerpc: Use instruction emulation infrastructure to handle alignment faultsPaul Mackerras1-771/+32
This replaces almost all of the instruction emulation code in fix_alignment() with calls to analyse_instr(), emulate_loadstore() and emulate_dcbz(). The only emulation code left is the SPE emulation code; analyse_instr() etc. do not handle SPE instructions at present. One result of this is that we can now handle alignment faults on all the new VSX load and store instructions that were added in POWER9. VSX loads/stores will take alignment faults for unaligned accesses to cache-inhibited memory. Another effect is that we no longer rely on the DAR and DSISR values set by the processor. With this, we now need to include the instruction emulation code unconditionally. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc: Fix DAR reporting when alignment handler faultsMichael Ellerman1-45/+74
Anton noticed that if we fault part way through emulating an unaligned instruction, we don't update the DAR to reflect that. The DAR value is eventually reported back to userspace as the address in the SEGV signal, and if userspace is using that value to demand fault then it can be confused by us not setting the value correctly. This patch is ugly as hell, but is intended to be the minimal fix and back ports easily. Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
2017-08-31powerpc/smp: Add Power9 scheduler topologyOliver O'Halloran1-1/+49
In previous generations of Power processors each core had a private L2 cache. The Power 9 processor has a slightly different design where the L2 cache is shared among pairs of cores rather than being completely private. Making the scheduler aware of this cache sharing allows the scheduler to make better migration decisions. For example, if two CPU heavy tasks share a core then one task can be migrated to the paired core to improve throughput. Under the existing three level topology the task could be migrated to any core on the same chip, while with the new topology it would be preferentially migrated to the paired core so it remains cache-hot. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/smp: Add cpu_l2_cache_mapOliver O'Halloran1-6/+17
We want to add an extra level to the CPU scheduler topology to account for cores which share a cache. To do this we need to build a cpumask for each CPU that indicates which CPUs share this cache to use as an input to the scheduler. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/smp: Rework CPU topology constructionOliver O'Halloran1-66/+86
The CPU scheduler topology is constructed from a number of per-cpu cpumasks which describe which sets of logical CPUs are related in some fashion. Current code that handles constructing these masks when CPUs are hot(un)plugged can be simplified a bit by exploiting the fact that the scheduler requires higher levels of the toplogy (e.g package level groupings) to be supersets of the lower levels (e.g. threas in a core). This patch reworks the cpumask construction to be simpler and easier to extend with extra topology levels. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> [mpe: Fix CONFIG_HOTPLUG_CPU=n build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/smp: Use cpu_to_chip_id() to find core siblingsOliver O'Halloran1-26/+11
When building the CPU scheduler topology the kernel uses the ibm,chipid property from the devicetree to group logical CPUs. Currently the DT search for this property is open-coded in smp.c and this functionality is a duplication of what's in cpu_to_chip_id() already. This patch removes the existing search in favor of that. It's worth mentioning that the semantics of the search are different in cpu_to_chip_id(). When there is no ibm,chipid in the CPUs node it will also search /cpus and / for the property, but this should not effect the output topology. Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/asm: Convert .llong directives to .8byteTobin C. Harding4-15/+15
.llong is an undocumented PPC specific directive. The generic equivalent is .quad, but even better (because it's self describing) is .8byte. Convert all .llong directives to .8byte. Signed-off-by: Tobin C. Harding <me@tobin.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc: Squash lines for simple wrapper functionsMasahiro Yamada1-30/+12
Remove unneeded variables and assignments. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/kernel: Change retrieval of pci_dnBryant G. Ly1-29/+4
For a PCI device it's pci_dn can be retrieved from pdev->dev.archdata.firmware_data, PCI_DN(devnode), or parent's list. Thus, we should just use the existing function pci_get_pdn_by_devfn to get the pci_dn. Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Reviewed-by: Sam Bobroff <sam.bobroff@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/pci: Remove OF node back pointer from pci_dnAlexey Kardashevskiy1-1/+0
The check_req() helper uses pci_get_pdn() to get an OF node pointer. pci_get_pdn() returns a pci_dn pointer which either: 1) from the OF node returned by pci_device_to_OF_node(); 2) from the parent child_list where entries don't have OF node pointers. Since check_req() does not care about 2), it can call pci_device_to_OF_node() directly, hence the change. The find_pe_dn() helper uses embedded pci_dn to get an OF node which is also stored in edev->pdev so let's take a shortcut and call pci_device_to_OF_node() directly. With these 2 changes, we can finally get rid of the OF node back pointer. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/eeh: Reduce use of pci_dn::nodeAlexey Kardashevskiy2-6/+10
The pci_dn struct caches a OF device node pointer in order to access the "ibm,loc-code" property when EEH is recovering. However, when this happens in eeh_dev_check_failure(), we also have a pci_dev pointer which should have a valid pointer to the device node when pci_dn has one (both pointers are not NULL for physical functions and are NULL for virtual functions). This changes pci_remove_device_node_info() to look for a parent of the node being removed, just like pci_add_device_node_info() does when it references the parent node. This is the first step to get rid of pci_dn::node. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/eeh: Remove unnecessary config_addr from eeh_devAlexey Kardashevskiy2-24/+21
The eeh_dev struct hold a config space address of an associated node and the very same address is also stored in the pci_dn struct which is always present during the eeh_dev lifetime. This uses bus:devfn directly from pci_dn instead of cached and packed config_addr. Since config_addr is made from device's bus:dev.fn, there is no point in keeping it in the debugfs either so remove that too. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/eeh: Remove unnecessary pointer to phb from eeh_devAlexey Kardashevskiy4-18/+17
The eeh_dev struct already holds a pointer to pci_dn which it does not exist without and pci_dn itself holds the very same pointer so just use it. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/eeh: Reduce to one the number of places where edev is allocatedAlexey Kardashevskiy1-11/+21
arch/powerpc/kernel/eeh_dev.c:57 is the only legit place where edev is allocated; other 2 places allocate it on stack and in the heap for a very short period of time to use eeh_pe_get() as takes edev. This changes eeh_pe_get() to receive required parameters explicitly. This removes unnecessary temporary allocation of edev. This uses the "pe_no" name instead of the "pe_config_addr" name as it actually is a PE number and not a config space address as it seemed. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/pci: Remove unused parameter from add_one_dev_pci_data()Alexey Kardashevskiy1-12/+2
pdev is always NULL, remove it. To make checkpatch.pl happy, this also removes the "out of memory" message. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc: Machine check interrupt is a non-maskable interruptNicholas Piggin1-3/+6
Use nmi_enter similarly to system reset interrupts. This uses NMI printk NMI buffers and turns off various debugging facilities that helps avoid tripping on ourselves or other CPUs. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/powernv: Use kernel crash path for machine checksNicholas Piggin2-1/+30
There are quite a few machine check exceptions that can be caused by kernel bugs. To make debugging easier, use the kernel crash path in cases of synchronous machine checks that occur in kernel mode, if that would not result in the machine going straight to panic or crash dump. There is a downside here that die()ing the process in kernel mode can still leave the system unstable. panic_on_oops will always force the system to fail-stop, so systems where that behaviour is important will still do the right thing. As a test, when triggering an i-side 0111b error (ifetch from foreign address) in kernel mode process context on POWER9, the kernel currently dies quickly like this: Severe Machine check interrupt [Not recovered] NIP [ffff000000000000]: 0xffff000000000000 Initiator: CPU Error type: Real address [Instruction fetch (foreign)] [ 127.426651616,0] OPAL: Reboot requested due to Platform error. Effective[ 127.426693712,3] OPAL: Reboot requested due to Platform error. address: ffff000000000000 opal: Reboot type 1 not supported Kernel panic - not syncing: PowerNV Unrecovered Machine Check CPU: 56 PID: 4425 Comm: syscall Tainted: G M 4.12.0-rc1-13857-ga4700a261072-dirty #35 Call Trace: [ 128.017988928,4] IPMI: BUG: Dropping ESEL on the floor due to buggy/mising code in OPAL for this BMC Rebooting in 10 seconds.. Trying to free IRQ 496 from IRQ context! After this patch, the process is killed and the kernel continues with this message, which gives enough information to identify the offending branch (i.e., with CFAR): Severe Machine check interrupt [Not recovered] NIP [ffff000000000000]: 0xffff000000000000 Initiator: CPU Error type: Real address [Instruction fetch (foreign)] Effective address: ffff000000000000 Oops: Machine check, sig: 7 [#1] SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 ... CPU: 22 PID: 4436 Comm: syscall Tainted: G M 4.12.0-rc1-13857-ga4700a261072-dirty #36 task: c000000932300000 task.stack: c000000932380000 NIP: ffff000000000000 LR: 00000000217706a4 CTR: ffff000000000000 REGS: c00000000fc8fd80 TRAP: 0200 Tainted: G M (4.12.0-rc1-13857-ga4700a261072-dirty) MSR: 90000000001c1003 <SF,HV,ME,RI,LE> CR: 24000484 XER: 20000000 CFAR: c000000000004c80 DAR: 0000000021770a90 DSISR: 0a000000 SOFTE: 1 GPR00: 0000000000001ebe 00007fffce4818b0 0000000021797f00 0000000000000000 GPR04: 00007fff8007ac24 0000000044000484 0000000000004000 00007fff801405e8 GPR08: 900000000280f033 0000000024000484 0000000000000000 0000000000000030 GPR12: 9000000000001003 00007fff801bc370 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR28: 00007fff801b0000 0000000000000000 00000000217707a0 00007fffce481918 NIP [ffff000000000000] 0xffff000000000000 LR [00000000217706a4] 0x217706a4 Call Trace: Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc: Do not send system reset request through the oops pathNicholas Piggin1-16/+31
A system reset is a request to crash / debug the system rather than necessarily caused by encountering a BUG. So there is no need to serialize all CPUs behind the die lock, adding taints to all subsequent traces beyond the first, breaking console locks, etc. The system reset is NMI context which has its own printk buffers to prevent output being interleaved. Then it's better to have all secondaries print out their debug as quickly as possible and the primary will flush out all printk buffers during panic(). So remove the 0x100 path from die, and move it into system_reset. Name the crash/dump reasons "System Reset". This gives "not tained" traces when crashing an untainted kernel. It also gives the panic reason as "System Reset" as opposed to "Fatal exception in interrupt" (or "die oops" for fadump). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc: Do not call ppc_md.panic in fadump panic notifierNicholas Piggin2-27/+22
If fadump is not registered, and no other crash or debug handlers are registered, the powerpc panic handler stops the guest before the generic panic code can push out debug information to the console. Currently, system reset injection causes the guest to silently stop. Stop calling ppc_md.panic in the panic notifier. crash_fadump already does rtas_os_term() to terminate the guest if fadump is registered. Remove ppc_md.panic. Move fadump panic notifier into fadump code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/64: Fix watchdog configuration regressionsNicholas Piggin2-7/+28
This fixes a couple more bits of fallout from the new hard lockup watchdog patch. It restores the required hw_nmi_get_sample_period() function for the perf watchdog, and removes some function declarations on 64e that are only defined for 64s. This fixes the 64e build when the hardlockup detector is enabled. It restores the default behaviour of disabling the perf watchdog, and also fixes disabling the 64s watchdog when running as a guest. Fixes: 2104180a53 ("powerpc/64s: implement arch-specific hardlockup watchdog") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/64s/radix: Do not allocate SLB shadow structuresNicholas Piggin1-2/+11
These are unused in radix mode. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31powerpc/64s/radix: Remove bolted-SLB address limit for per-cpu stacksNicholas Piggin1-3/+8
Radix MMU does not take SLB or TLB interrupts when accessing kernel linear address. Remove this restriction for radix mode. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-29powerpc/64s: idle POWER9 can execute stop in virtual modeNicholas Piggin1-0/+9
The hardware can execute stop in any context, and KVM does not require real mode because siblings do not share MMU state. This saves a switch to real-mode when going idle. Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-29powerpc/64s: Drop no longer used IDLE_STATE_ENTER_SEQNicholas Piggin1-4/+1
There are no longer any callers of IDLE_STATE_ENTER_SEQ, all callers use IDLE_STATE_ENTER_SEQ_NORET. So drop the former. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Split out of larger patch, write change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-29powerpc/64s: POWER9 can execute stop without a sync sequenceNicholas Piggin1-3/+4
We don't need to use IDLE_STATE_ENTER_SEQ_NORET on Power9. Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Split out of larger patch] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-29powerpc/64s: Move IDLE_STATE_ENTER_SEQ[_NORET] into idle_book3s.SNicholas Piggin1-0/+17
This macro is only used in idle_book3s.S, move it in there and add a more descriptive comment. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Split out of larger patch and write change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-29Merge branch 'topic/ppc-kvm' into nextMichael Ellerman1-11/+24
Merge Nicks commit to rework the KVM thread management, shared with the KVM tree via the ppc-kvm topic branch.
2017-08-29KVM: PPC: Book3S HV: POWER9 does not require secondary thread managementNicholas Piggin1-11/+24
POWER9 CPUs have independent MMU contexts per thread, so KVM does not need to quiesce secondary threads, so the hwthread_req/hwthread_state protocol does not have to be used. So patch it away on POWER9, and patch away the branch from the Linux idle wakeup to kvm_start_guest that is never used. Add a warning and error out of kvmppc_grab_hwthread in case it is ever called on POWER9. This avoids a hwsync in the idle wakeup path on POWER9. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> [mpe: Use WARN(...) instead of WARN_ON()/pr_err(...)] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-28powerpc/e6500: Update machine check for L1D cache errMatt Weber1-2/+10
This patch updates the machine check handler of Linux kernel to handle the e6500 architecture case. In e6500 core, L1 Data Cache Write Shadow Mode (DCWS) register is not implemented but L1 data cache always runs in write shadow mode. So, on L1 data cache parity errors, hardware will automatically invalidate the data cache but will still log a machine check interrupt. Signed-off-by: Ronak Desai <ronak.desai@rockwellcollins.com> Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com> Signed-off-by: Scott Wood <oss@buserror.net>
2017-08-28powerpc/oops: Line up NIP & MSR with other rowsMichael Ellerman1-2/+2
This is purely cosmetic, but does look nicer IMHO: Before: task: c000000001453400 task.stack: c000000001c6c000 NIP: c000000000a0fbfc LR: c000000000a0fbf4 CTR: c000000000ba6220 REGS: c0000001fffef820 TRAP: 0300 Not tainted (4.13.0-rc6-gcc-6.3.1-00234-g423af27f7d81) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 88088242 XER: 00000000 CFAR: c0000000000b3488 DAR: 0000000000000000 DSISR: 42000000 SOFTE: 0 After: task: c000000001453400 task.stack: c000000001c6c000 NIP: c000000000a0fbfc LR: c000000000a0fbf4 CTR: c000000000ba6220 REGS: c0000001fffef820 TRAP: 0300 Not tainted (4.13.0-rc6-gcc-6.3.1-00234-g423af27f7d81-dirty) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 88088242 XER: 00000000 CFAR: c0000000000b34a4 DAR: 0000000000000000 DSISR: 42000000 SOFTE: 0 Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-28powerpc/oops: Print CR/XER on same line as MSRMichael Ellerman1-1/+1
Somehow we missed this when the pr_cont() changes went in. Fix CR/XER to go on the same line as MSR, as they have historically, eg: MSR: 8000000000009032 <SF,EE,ME,IR,DR,RI> CR: 4804408a XER: 20000000 Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-28powerpc/oops: Use IS_ENABLED() for oops markersMichael Ellerman1-9/+10
Just because it looks less gross. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-28powerpc/oops: Print the kernel's endian in the oopsMichael Ellerman1-0/+6
Although the MSR tells you what endian you're in it's possible that isn't the same endian the kernel was built for, and if that happens you're usually having a very bad day. So print a marker to make it 100% clear which endian the kernel was built for. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-28powerpc/oops: Fix the oops markers to use pr_cont()Michael Ellerman1-5/+5
When we oops we print a few markers for significant config options such as PREEMPT, SMP etc. Currently these appear on separate lines because we're not using pr_cont() properly. Fix it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-24powerpc/uprobes: Implement arch_uretprobe_is_alive()Naveen N. Rao1-0/+9
This helper is used to detect if a uprobe'd function has returned through a setjmp/longjmp, rather than branching to the LR that was updated previously by us. This fixes a SIGSEGV that gets generated when programs use setjmp/longjmp with uretprobes. We use the arm64 model (arch/arm64/kernel/probes/uprobes.c: arch_uretprobe_is_alive()) for detecting when stack frames have been removed from under us. Reference: https://marc.info/?l=linux-kernel&m=143748610330073 commit 7b868e4802a86 ("uprobes/x86: Reimplement arch_uretprobe_is_alive()") commit db087ef69a2b1 ("uprobes/x86: Make arch_uretprobe_is_alive(RP_CHECK_CALL) more clever") Tested with the test program from: https://sourceware.org/git/gitweb.cgi?p=systemtap.git;a=blob;f=testsuite/systemtap.base/bz5274.c;hb=HEAD And this script: $ cat test.sh #!/bin/bash perf probe -x ./bz5274 -a bz5274_main_return=main%return perf probe -x ./bz5274 -a bz5274_funca_return=funca%return perf probe -x ./bz5274 -a bz5274_funcb_return=funcb%return perf probe -x ./bz5274 -a bz5274_funcc_return=funcc%return perf probe -x ./bz5274 -a bz5274_funcd_return=funcd%return perf record -e 'probe_bz5274:*' -aR ./bz5274 Reported-by: Gustavo Luiz Duarte <gduarte@redhat.com> Reported-by: zsun@redhat.com Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-24powerpc/kprobes: Don't save/restore DAR/DSISR to/from pt_regs for optprobesNaveen N. Rao1-8/+0
We don't save/restore these across a trap, or with KPROBES_ON_FTRACE. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23powerpc/64: Optimise set/clear of CTRL[RUN] (runlatch)Nicholas Piggin1-8/+27
On modern CPUs the CTRL register is read-only except bit 63 which is the run latch control. This means it can be updated with a mtspr rather than mfspr/mtspr. To accomodate older CPUs (Cell at least), where there are other bits in the register, we still do a read/modify/write on pre 2.06 CPUs. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Update change log to mention 2.06 workaround] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>