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2018-02-02Merge tag 'powerpc-4.16-1' of ↵Linus Torvalds1-5/+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 ...
2018-01-22signal/powerpc: Remove unnecessary signal_code parameter of do_send_trapEric W. Biederman1-6/+6
signal_code is always TRAP_HWBKPT Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-22powerpc/pseries, ps3: panic flush kernel messages before halting systemNicholas Piggin1-0/+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>
2018-01-22powerpc: Use octal numbers for file permissionsRussell Currey1-2/+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>
2018-01-20powerpc/ptrace: Add memory protection key regsetThiago Jung Bauermann1-0/+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>
2018-01-20powerpc: Deliver SEGV signal on pkey violationRam Pai1-1/+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>
2018-01-18powerpc: System reset avoid interleaving oops using die synchronisationNicholas Piggin1-1/+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>
2018-01-16powerpc: Use the TRAP macro whenever comparing a trap numberBenjamin Herrenschmidt1-1/+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>
2018-01-12signal/powerpc: Document conflicts with SI_USER and SIGFPE and SIGTRAPEric W. Biederman1-5/+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>
2017-11-06powerpc: Remove facility loadups on transactional {fp, vec, vsx} unavailableCyril Bur1-30/+0
After handling a transactional FP, Altivec or VSX unavailable exception. The return to userspace code will detect that the TIF_RESTORE_TM bit is set and call restore_tm_state(). restore_tm_state() will call restore_math() to ensure that the correct facilities are loaded. This means that all the loadup code in {fp,altivec,vsx}_unavailable_tm() is doing pointless work and can simply be removed. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06powerpc: Always save/restore checkpointed regs during treclaim/trecheckpointCyril Bur1-20/+6
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>
2017-11-06powerpc: Force reload for recheckpoint during tm {fp, vec, vsx} unavailable ↵Cyril Bur1-5/+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>
2017-11-06powerpc: Don't enable FP/Altivec if not checkpointedCyril Bur1-4/+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>
2017-11-06powerpc/tm: Don't check for WARN in TM Bad Thing handlingMichael Ellerman1-7/+2
Currently when we take a TM Bad Thing program check exception, we search the bug table to see if the program check was generated by a WARN/WARN_ON etc. That makes no sense, the WARN macros use trap instructions, which should never generate a TM Bad Thing exception. If they ever did that would be a bug and we should oops. We do have some hand-coded bugs in tm.S, using EMIT_BUG_ENTRY, but those are all BUGs not WARNs, and they all use trap instructions anyway. Almost certainly this check was incorrectly copied from the REASON_TRAP handling in the same function. Remove it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-By: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-27powerpc/64s: Add workaround for P9 vector CI load issueMichael Neuling1-0/+201
POWER9 DD2.1 and earlier has an issue where some cache inhibited vector load will return bad data. The workaround is two part, one firmware/microcode part triggers HMI interrupts when hitting such loads, the other part is this patch which then emulates the instructions in Linux. The affected instructions are limited to lxvd2x, lxvw4x, lxvb16x and lxvh8x. When an instruction triggers the HMI, all threads in the core will be sent to the HMI handler, not just the one running the vector load. In general, these spurious HMIs are detected by the emulation code and we just return back to the running process. Unfortunately, if a spurious interrupt occurs on a vector load that's to normal memory we have no way to detect that it's spurious (unless we walk the page tables, which is very expensive). In this case we emulate the load but we need do so using a vector load itself to ensure 128bit atomicity is preserved. Some additional debugfs emulated instruction counters are added also. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [mpe: Switch CONFIG_PPC_BOOK3S_64 to CONFIG_VSX to unbreak the build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-20Merge branch 'next' of ↵Michael Ellerman1-2/+10
git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into fixes Merge one commit from Scott which I missed while away.
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 Piggin1-0/+22
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>
2017-08-28powerpc/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: 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>
2017-08-10powerpc/8xx: Remove SoftwareEmulation()Christophe Leroy1-18/+0
Since commit aa42c69c67f82 ("[POWERPC] Add support for FP emulation for the e300c2 core"), program_check_exception() can be called for math emulation. In that case, 'reason' is 0. On the 8xx, there is a Software Emulation interrupt which is called for all unimplemented and illegal instructions. This interrupt calls SoftwareEmulation() which does almost the same as program_check_exception() called with reason = 0. The Software Emulation interrupt sets all reason bits to 0, it is therefore possible to call program_check_exception() directly from the interrupt handler. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/8xx: Move 8xx machine check handlers into platforms/8xxChristophe Leroy1-25/+0
In the same spirit as what was done for 4xx and 44x, move the 8xx machine check into platforms/8xx Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/traps: Use SRR1 defines for program check reasonsMichael Ellerman1-5/+5
Currently we open code the reason codes for program checks. Instead use the existing SRR1 defines. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/mce: Move 64-bit machine check code into mce.cMichael Ellerman1-33/+0
We already have mce.c which is built for 64bit and contains other parts of the machine check code, so move these bits in there too. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/traps: machine_check_generic() is only used on 32-bitMichael Ellerman1-1/+1
Make it clear that the fallback version of machine_check_generic() is only used on 32-bit configs. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/traps: Inline get_mc_reason()Michael Ellerman1-10/+4
get_mc_reason() no longer provides (if it ever really did) any meaningful abstraction, so remove it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/4xx: Move machine_check_4xx() into platforms/4xxMichael Ellerman1-17/+1
Now that we have 4xx platform directory we can move the 4xx machine check handler in there. Again we drop get_mc_reason() and replace it with regs->dsisr directly (which is actually SPRN_ESR). Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/44x: Move 44x machine check handlers into platforms/44xMichael Ellerman1-74/+0
We have several 44x machine check handlers defined in traps.c. It would be preferable if they were split out with the platforms that use them. Do that. In the process, drop get_mc_reason() and instead just open code the lookup of reason from regs->dsisr. This avoids a pointless layer of abstraction. We know to use regs->dsisr because 44x enables BOOKE which enables PPC_ADV_DEBUG_REGS, and FSL_BOOKE is not enabled on 44x builds. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc: Add irq accounting for system reset interruptsNicholas Piggin1-0/+2
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10powerpc/64s: Fix mce accounting for powernvNicholas Piggin1-1/+3
On 64-bit Book3s, when we're in HV mode, we have already counted the machine check exception in machine_check_early(). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Use IS_ENABLED() rather than an #ifdef] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-03powerpc/64s: Blacklist functions invoked on a trapNaveen N. Rao1-0/+3
Blacklist all functions involved while handling a trap. We: - convert some of the symbols into private symbols, and - blacklist most functions involved while handling a trap. Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-03powerpc/book3s/mce: Move add_taint() later in virtual modeMahesh Salgaonkar1-2/+2
machine_check_early() gets called in real mode. The very first time when add_taint() is called, it prints a warning which ends up calling opal call (that uses OPAL_CALL wrapper) for writing it to console. If we get a very first machine check while we are in opal we are doomed. OPAL_CALL overwrites the PACASAVEDMSR in r13 and in this case when we are done with MCE handling the original opal call will use this new MSR on it's way back to opal_return. This usually leads to unexpected behaviour or the kernel to panic. Instead move the add_taint() call later in the virtual mode where it is safe to call. This is broken with current FW level. We got lucky so far for not getting very first MCE hit while in OPAL. But easily reproducible on Mambo. Fixes: 27ea2c420cad ("powerpc: Set the correct kernel taint on machine check errors.") Cc: stable@vger.kernel.org # v4.2+ Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc: Mark system reset as an NMI with nmi_enter/exit()Nicholas Piggin1-0/+11
System reset is a non-maskable interrupt from Linux's point of view (occurs under local_irq_disable()), so it should use nmi_enter/exit. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-28powerpc/64s: Disallow system reset vs system reset reentrancyNicholas Piggin1-1/+7
In preparation for using a dedicated stack for system reset interrupts, prevent a nested system reset from recovering, in order to simplify code that is called in crash/debug path. This allows a system reset interrupt to just use the base stack pointer. Keep an in_nmi nesting counter similarly to the in_mce counter. Consider the interrrupt non-recoverable if it is taken inside another system reset. Interrupt nesting could be allowed similarly to MCE, but system reset is a special case that's not for normal operation, so simplicity wins until there is requirement for nested system reset interrupts. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13powerpc/64s: Add SCV FSCR bit for ISA v3.0Nicholas Piggin1-0/+1
Add the bit definition and use it in facility_unavailable_exception() so we can intelligently report the cause if we take a fault for SCV. This doesn't actually enable SCV. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Drop whitespace changes to the existing entries, flush out change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-13powerpc/64s: Add msgp facility unavailable log stringNicholas Piggin1-0/+1
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-11powerpc: Create asm/debugfs.h and move powerpc_debugfs_root thereMichael Ellerman1-1/+1
powerpc_debugfs_root is the dentry representing the root of the "powerpc" directory tree in debugfs. Currently it sits in asm/debug.h, a long with some other things that have "debug" in the name, but are otherwise unrelated. Pull it out into a separate header, which also includes linux/debugfs.h, and convert all the users to include debugfs.h instead of debug.h. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+1
<linux/sched/debug.h> We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds1-1/+1
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-02powerpc Don't print misleading facility name in facility unavailable exceptionBalbir Singh1-4/+4
The current facility_strings[] are correct when the trap address is 0xf80 (hypervisor facility unavailable). When the trap address is 0xf60 (facility unavailable) IC (Interruption Cause) a.k.a status in the code is undefined for values 0 and 1. Add a check to prevent printing the (misleading) facility name for IC 0 and 1 when we came in via 0xf60. In all cases, print the actual IC value, to avoid any confusion. This hasn't been seen on real hardware, on only qemu which was misreporting an exception. Signed-off-by: Balbir Singh <bsingharora@gmail.com> [mpe: Fix indentation, combine printks(), massage change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-30powerpc: Change places using CONFIG_KEXEC to use CONFIG_KEXEC_CORE instead.Thiago Jung Bauermann1-1/+1
Commit 2965faa5e03d ("kexec: split kexec_load syscall from kexec core code") introduced CONFIG_KEXEC_CORE so that CONFIG_KEXEC means whether the kexec_load system call should be compiled-in and CONFIG_KEXEC_FILE means whether the kexec_file_load system call should be compiled-in. These options can be set independently from each other. Since until now powerpc only supported kexec_load, CONFIG_KEXEC and CONFIG_KEXEC_CORE were synonyms. That is not the case anymore, so we need to make a distinction. Almost all places where CONFIG_KEXEC was being used should be using CONFIG_KEXEC_CORE instead, since kexec_file_load also needs that code compiled in. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-23powerpc/kprobes: Invoke handlers directlyNaveen N. Rao1-0/+13
Invoke the kprobe handlers directly rather than through notify_die(), to reduce path taken for handling kprobes. Similar to commit 6f6343f53d13 ("kprobes/x86: Call exception handlers directly from do_int3/do_debug"). While at it, rename post_kprobe_handler() to kprobe_post_handler() for more uniform naming. Reported-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-18powerpc: Fix second nested oops hangNicholas Piggin1-2/+3
When ending an oops, don't clear die_owner unless the nest count went to zero. This prevents a second nested oops from hanging forever on the die_lock. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-18powerpc: Fix graceful debugger recoveryNicholas Piggin1-4/+5
When exiting xmon with 'x' (exit and recover), oops_begin bails out immediately, but die then calls __die() and oops_end(), which cause a lot of bad things to happen. If the debugger was attached then went to graceful recovery, exit from die() immediately. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-14powerpc: Revert Load Monitor Register SupportMichael Neuling1-9/+0
Load monitored is no longer supported on POWER9 so let's remove the code. This reverts commit bd3ea317fddf ("powerpc: Load Monitor Register Support"). Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-14powerpc: Add support for relative exception tablesNicholas Piggin1-1/+1
This halves the exception table size on 64-bit builds, and it allows build-time sorting of exception tables to work on relocated kernels. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Minor asm fixups and bits to keep the selftests working] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-10-11Merge branch 'next' of ↵Michael Ellerman1-16/+29
git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next Freescale updates from Scott: "Highlights include qbman support (a prerequisite for datapath drivers such as ethernet), a PCI DMA fix+improvement, reset handler changes, more 8xx optimizations, and some cleanups and fixes."