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2018-02-02Merge tag 'powerpc-4.16-1' of ↵Linus Torvalds
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 ...
2018-01-27powerpc/kernel: Block interrupts when updating TIDRSukadev Bhattiprolu
clear_thread_tidr() is called in interrupt context as a part of delayed put of the task structure (i.e as a part of timer interrupt). To prevent a deadlock, block interrupts when holding vas_thread_id_lock to set/ clear TIDR for a task. Fixes: ec233ede4c86 ("powerpc: Add support for setting SPRN_TIDR") Cc: stable@vger.kernel.org # v4.15+ Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-22signal/ptrace: Add force_sig_ptrace_errno_trap and use it where neededEric W. Biederman
There are so many places that build struct siginfo by hand that at least one of them is bound to get it wrong. A handful of cases in the kernel arguably did just that when using the errno field of siginfo to pass no errno values to userspace. The usage is limited to a single si_code so at least does not mess up anything else. Encapsulate this questionable pattern in a helper function so that the userspace ABI is preserved. Update all of the places that use this pattern to use the new helper function. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-22signal/powerpc: Remove unnecessary signal_code parameter of do_send_trapEric W. Biederman
signal_code is always TRAP_HWBKPT Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-21Merge branch 'fixes' into nextMichael Ellerman
Merge our fixes branch from the 4.15 cycle. Unusually the fixes branch saw some significant features merged, notably the RFI flush patches, so we want the code in next to be tested against that, to avoid any surprises when the two are merged. There's also some other work on the panic handling that was reverted in fixes and we now want to do properly in next, which would conflict. And we also fix a few other minor merge conflicts.
2018-01-20powerpc: store and restore the pkey state across context switchesRam Pai
Store and restore the AMR, IAMR and UAMOR register state of the task before scheduling out and after scheduling in, respectively. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19cxl: Add support for ASB_Notify on POWER9Christophe Lombard
The POWER9 core supports a new feature: ASB_Notify which requires the support of the Special Purpose Register: TIDR. The ASB_Notify command, generated by the AFU, will attempt to wake-up the host thread identified by the particular LPID:PID:TID. This patch assign a unique TIDR (thread id) for the current thread which will be used in the process element entry. Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Reviewed-by: Philippe Bergheaud <felix@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19powerpc/64: Add #defines for paca->soft_enabled flagsMadhavan Srinivasan
Two #defines IRQS_ENABLED and IRQS_DISABLED are added to be used when updating paca->soft_enabled. Replace the hardcoded values used when updating paca->soft_enabled with IRQ_(EN|DIS)ABLED #define. No logic change. Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16powerpc: Use the TRAP macro whenever comparing a trap numberBenjamin Herrenschmidt
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>
2017-12-19powerpc/kernel: Print actual address of regs when oopsingMichael Ellerman
When we oops or otherwise call show_regs() we print the address of the regs structure. Being able to see the address is fairly useful, firstly to verify that the regs pointer is not completely bogus, and secondly it allows you to dump the regs and surrounding memory with a debugger if you have one. In the normal case the regs will be located somewhere on the stack, so printing their location discloses no further information than printing the stack pointer does already. So switch to %px and print the actual address, not the hashed value. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-29powerpc: Do not assign thread.tidr if already assignedVaibhav Jain
If set_thread_tidr() is called twice for same task_struct then it will allocate a new tidr value to it leaving the previous value still dangling in the vas_thread_ida table. To fix this the patch changes set_thread_tidr() to check if a tidr value is already assigned to the task_struct and if yes then returns zero. Fixes: ec233ede4c86("powerpc: Add support for setting SPRN_TIDR") Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> [mpe: Modify to return 0 in the success case, not the TID value] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-29powerpc: Avoid signed to unsigned conversion in set_thread_tidr()Vaibhav Jain
There is an unsafe signed to unsigned conversion in set_thread_tidr() that may cause an error value to be assigned to SPRN_TIDR register and used as thread-id. The issue happens as assign_thread_tidr() returns an int and thread.tidr is an unsigned-long. So a negative error code returned from assign_thread_tidr() will fail the error check and gets assigned as tidr as a large positive value. To fix this the patch assigns the return value of assign_thread_tidr() to a temporary int and assigns it to thread.tidr iff its '> 0'. The patch shouldn't impact the calling convention of set_thread_tidr() i.e all -ve return-values are error codes and a return value of '0' indicates success. Fixes: ec233ede4c86("powerpc: Add support for setting SPRN_TIDR") Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Reviewed-by: Christophe Lombard clombard@linux.vnet.ibm.com Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc: Define set_thread_uses_vas()Sukadev Bhattiprolu
A CP_ABORT instruction is required in processes that have mapped a VAS "paste address" with the intention of using COPY/PASTE instructions. But since CP_ABORT is expensive, we want to restrict it to only processes that use/intend to use COPY/PASTE. Define an interface, set_thread_uses_vas(), that VAS can use to indicate that the current process opened a send window. During context switch, issue CP_ABORT only for processes that have the flag set. Thanks for input from Nick Piggin, Michael Ellerman. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> [mpe: Fix to not use new_thread after _switch() returns] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc: Add support for setting SPRN_TIDRSukadev Bhattiprolu
We need the SPRN_TIDR to be set for use with fast thread-wakeup (core- to-core wakeup) and also with CAPI. Each thread in a process needs to have a unique id within the process. But for now, we assign globally unique thread ids to all threads in the system. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com> Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> [mpe: Simplify tidr clearing on fork() and ctx switch code] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06powerpc: Always save/restore checkpointed regs during treclaim/trecheckpointCyril Bur
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 Bur
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 Bur
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/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64Michael Ellerman
CONFIG_PPC_STD_MMU_64 indicates support for the "standard" powerpc MMU on 64-bit CPUs. The "standard" MMU refers to the hash page table MMU found in "server" processors, from IBM mainly. Currently CONFIG_PPC_STD_MMU_64 is == CONFIG_PPC_BOOK3S_64. While it's annoying to have two symbols that always have the same value, it's not quite annoying enough to bother removing one. However with the arrival of Power9, we now have the situation where CONFIG_PPC_STD_MMU_64 is enabled, but the kernel is running using the Radix MMU - *not* the "standard" MMU. So it is now actively confusing to use it, because it implies that code is disabled or inactive when the Radix MMU is in use, however that is not necessarily true. So s/CONFIG_PPC_STD_MMU_64/CONFIG_PPC_BOOK3S_64/, and do some minor formatting updates of some of the affected lines. This will be a pain for backports, but c'est la vie. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-21powerpc/tm: P9 disable transactionally suspended sigcontextsMichael Neuling
Unfortunately userspace can construct a sigcontext which enables suspend. Thus userspace can force Linux into a path where trechkpt is executed. This patch blocks this from happening on POWER9 by sanity checking sigcontexts passed in. ptrace doesn't have this problem as only MSR SE and BE can be changed via ptrace. This patch also adds a number of WARN_ON()s in case we ever enter suspend when we shouldn't. This should not happen, but if it does the symptoms are soft lockup warnings which are not obviously TM related, so the WARN_ON()s should make it obvious what's happening. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-21powerpc/powernv: Enable TM without suspend if possibleMichael Ellerman
Some Power9 revisions can run in a mode where TM operates without suspended state. If we find ourself on a CPU that might be in this mode, we query OPAL to check, and if so we reenable TM in CPU features, and enable a new user feature to signal to userspace that we are in this mode. We do not enable the "normal" user feature, PPC_FEATURE2_HTM, but we do enable PPC_FEATURE2_HTM_NOSC because that indicates to userspace that the kernel will abort transactions on syscall entry, which is true regardless of the suspend mode. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-06powerpc: get_wchan(): solve possible race scenario due to parallel wakeupKautuk Consul
Add a check for p->state == TASK_RUNNING so that any wake-ups on task_struct p in the interim lead to 0 being returned by get_wchan(). Signed-off-by: Kautuk Consul <kautuk.consul.1980@gmail.com> [mpe: Confirmed other architectures do similar] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-28powerpc/oops: Line up NIP & MSR with other rowsMichael Ellerman
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 Ellerman
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>
2017-08-23powerpc/64: Optimise set/clear of CTRL[RUN] (runlatch)Nicholas Piggin
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>
2017-08-23Merge branch 'fixes' into nextMichael Ellerman
There's a non-trivial dependency between some commits we want to put in next and the KVM prefetch work around that went into fixes. So merge fixes into next.
2017-08-16powerpc: Remove more redundant VSX save/testsBenjamin Herrenschmidt
__giveup_vsx/save_vsx are completely equivalent to testing MSR_FP and MSR_VEC and calling the corresponding giveup/save function so just remove the spurious VSX cases. Also add WARN_ONs checking that we never have VSX enabled without the two other. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16powerpc: Remove redundant clear of MSR_VSX in __giveup_vsx()Benjamin Herrenschmidt
__giveup_fpu() already does it and we cannot have MSR_VSX set without having MSR_FP also set. This also adds a warning to check we indeed do Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16powerpc: Remove redundant FP/Altivec giveup codeBenjamin Herrenschmidt
__giveup_vsx() already calls those two functions. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16powerpc: Fix missing newline before {Benjamin Herrenschmidt
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16powerpc: Fix VSX enabling/flushing to also test MSR_FP and MSR_VECBenjamin Herrenschmidt
VSX uses a combination of the old vector registers, the old FP registers and new "second halves" of the FP registers. Thus when we need to see the VSX state in the thread struct (flush_vsx_to_thread()) or when we'll use the VSX in the kernel (enable_kernel_vsx()) we need to ensure they are all flushed into the thread struct if either of them is individually enabled. Unfortunately we only tested if the whole VSX was enabled, not if they were individually enabled. Fixes: 72cd7b44bc99 ("powerpc: Uncomment and make enable_kernel_vsx() routine available") Cc: stable@vger.kernel.org # v4.3+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-07Revert "powerpc/64: Avoid restore_math call if possible in syscall exit"Michael Ellerman
This reverts commit bc4f65e4cf9d6cc43e0e9ba0b8648cf9201cd55f. As reported by Andreas, this commit is causing unrecoverable SLB misses in the system call exit path: Unrecoverable exception 4100 at c00000000000a1ec Oops: Unrecoverable exception, sig: 6 [#1] SMP NR_CPUS=2 PowerMac ... CPU: 0 PID: 18626 Comm: rm Not tainted 4.13.0-rc3 #1 task: c00000018335e080 task.stack: c000000139e50000 NIP: c00000000000a1ec LR: c00000000000a118 CTR: 0000000000000000 REGS: c000000139e53bb0 TRAP: 4100 Not tainted (4.13.0-rc3) MSR: 9000000000001030 <SF,HV,ME,IR,DR> CR: 24000044 XER: 20000000 SOFTE: 1 GPR00: 0000000000000000 c000000139e53e30 c000000000abb500 fffffffffffffffe GPR04: c0000001eb866298 0000000000000000 0000000000000000 c00000018335e080 GPR08: 900000000000d032 0000000000000000 0000000000000002 fffffffffffff001 GPR12: c000000139e50000 c00000000ffff000 00003fffa8c0dca0 00003fffa8c0dc88 GPR16: 0000000010000000 0000000000000001 00003fffa8c0eaa0 0000000000000000 GPR20: 00003fffa8c27528 00003fffa8c27b00 0000000000000000 0000000000000000 GPR24: 00003fffa8c0d918 00003ffff1b3efa0 00003fffa8c26d68 0000000000000000 GPR28: 00003fffa8c249e8 00003fffa8c263d0 00003fffa8c27550 00003ffff1b3ef10 NIP [c00000000000a1ec] system_call_exit+0xc0/0x21c LR [c00000000000a118] system_call+0x58/0x6c Call Trace: [c000000139e53e30] [c00000000000a118] system_call+0x58/0x6c (unreliable) Instruction dump: 64a51000 7c6300d0 f8a101a0 4bffff9c 3c000000 60000006 780007c6 64000000 60000000 7c004039 4082001c e8ed0170 <88070b78> 88c70b79 7c003214 2c200000 This is caused by us trying to load THREAD_LOAD_FP with MSR_RI=0, and taking an SLB miss on the thread struct. Reported-by: Andreas Schwab <schwab@linux-m68k.org> Diagnosed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-03Merge branch 'fixes' into nextMichael Ellerman
Merge our fixes branch, a few of them are tripping people up while working on top of next, and we also have a dependency between the CXL fixes and new CXL code we want to merge into next.
2017-06-15powerpc/64s: Avoid cpabort in context switch when possibleNicholas Piggin
The ISA v3.0B copy-paste facility only requires cpabort when switching to a process that has foreign real addresses mapped (direct access to accelerators), to clear a potential copy buffer filled by a previous thread. There is no accelerator driver implemented yet, so cpabort can be removed. It can be be re-added when a driver is implemented. POWER9 DD1 requires the copy buffer to always be cleared on context switch, but if accelerators are not in use, then an unpaired copy from a dummy region is sufficient to clear data out of the copy buffer. This increases context switch performance by about 5% on POWER9. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-15powerpc/64s: Leave interrupts hard enabled in context switch for radixNicholas Piggin
Commit 4387e9ff25 ("[POWERPC] Fix PMU + soft interrupt disable bug") hard disabled interrupts over the low level context switch, because the SLB management can't cope with a PMU interrupt accesing the stack in that window. Radix based kernel mapping does not use the SLB so it does not require interrupts hard disabled here. This is worth 1-2% in context switch performance on POWER9. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-15powerpc/64: Avoid restore_math call if possible in syscall exitNicholas Piggin
The syscall exit code that branches to restore_math is quite heavy on Book3S, consisting of 2 mtmsr instructions. Threads that don't use both FP and vector can get caught here if the kernel ever uses FP or vector. Lazy-FP/vec context switching also trips this case. So check for lazy FP and vector before switching RI for restore_math. Move most of this case out of line. For threads that do want to restore math registers, the MSR switches are still suboptimal. Future direction may be to use a soft-RI bit to avoid MSR switches in kernel (similar to soft-EE), but for now at least the no-restore POWER9 context switch rate increases by about 5% due to sched_yield(2) return performance. I haven't constructed a test to measure the syscall cost. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-06powerpc/kernel: Initialize load_tm on task creationBreno Leitao
Currently tsk->thread.load_tm is not initialized in the task creation and can contain garbage on a new task. This is an undesired behaviour, since it affects the timing to enable and disable the transactional memory laziness (disabling and enabling the MSR TM bit, which affects TM reclaim and recheckpoint in the scheduling process). Fixes: 5d176f751ee3 ("powerpc: tm: Enable transactional memory (TM) lazily for userspace") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-05powerpc/kernel: Fix FP and vector register restorationBreno Leitao
Currently tsk->thread->load_vec and load_fp are not initialized during task creation, which can lead to garbage values in these variables (non-zero values). These variables will be checked later in restore_math() to validate if the FP and vector registers are being utilized. Since these values might be non-zero, the restore_math() will continue to save the FP and vectors even if they were never utilized by the userspace application. load_fp and load_vec counters will then overflow (they wrap at 255) and the FP and Altivec will be finally disabled, but before that condition is reached (counter overflow) several context switches will have restored FP and vector registers without need, causing a performance degradation. Fixes: 70fe3d980f5f ("powerpc: Restore FPU/VEC/VSX if previously used") Cc: stable@vger.kernel.org # v4.6+ Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Gustavo Romero <gusbromero@gmail.com> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-15powerpc/tm: Fix FP and VMX register corruptionMichael Neuling
In commit dc3106690b20 ("powerpc: tm: Always use fp_state and vr_state to store live registers"), a section of code was removed that copied the current state to checkpointed state. That code should not have been removed. When an FP (Floating Point) unavailable is taken inside a transaction, we need to abort the transaction. This is because at the time of the tbegin, the FP state is bogus so the state stored in the checkpointed registers is incorrect. To fix this, we treclaim (to get the checkpointed GPRs) and then copy the thread_struct FP live state into the checkpointed state. We then trecheckpoint so that the FP state is correctly restored into the CPU. The copying of the FP registers from live to checkpointed is what was missing. This simplifies the logic slightly from the original patch. tm_reclaim_thread() will now always write the checkpointed FP state. Either the checkpointed FP state will be written as part of the actual treclaim (in tm.S), or it'll be a copy of the live state. Which one we use is based on MSR[FP] from userspace. Similarly for VMX. Fixes: dc3106690b20 ("powerpc: tm: Always use fp_state and vr_state to store live registers") Cc: stable@vger.kernel.org # 4.9+ Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: cyrilbur@gmail.com Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/task_stack.h> We are going to split <linux/sched/task_stack.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/task_stack.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>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/task.h> We are going to split <linux/sched/task.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/task.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>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<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>
2017-03-01Merge tag 'powerpc-4.11-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull more powerpc updates from Michael Ellerman: "Highlights include: - an update of the disassembly code used by xmon to the latest versions in binutils. We've received permission from all the authors of the relevant binutils changes to relicense their changes to the relevant files from GPLv3 to GPLv2, for inclusion in Linux. Thanks to Peter Bergner for doing the leg work to get permission from everyone. - addition of the "architected" Power9 CPU table entry, allowing us to boot in Power9 architected mode under a hypervisor. - updates to the Power9 PMU code. - implementation of clear_bit_unlock_is_negative_byte() to optimise unlock_page(). - Freescale updates from Scott: "Highlights include 8xx breakpoints and perf, t1042rdb display support, and board updates." Thanks to: Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Balbir Singh, Douglas Miller, Frédéric Weisbecker, Gavin Shan, Madhavan Srinivasan, Michael Roth, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Peter Bergner, Paul E. McKenney, Rashmica Gupta, Russell Currey, Sahil Mehta, Stewart Smith" * tag 'powerpc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (48 commits) powerpc: Remove leftover cputime_to_nsecs call causing build error powerpc/mm/hash: Always clear UPRT and Host Radix bits when setting up CPU powerpc/optprobes: Fix TOC handling in optprobes trampoline powerpc/pseries: Advertise Hot Plug Event support to firmware cxl: fix nested locking hang during EEH hotplug powerpc/xmon: Dump memory in CPU endian format powerpc/pseries: Revert 'Auto-online hotplugged memory' powerpc/powernv: Make PCI non-optional powerpc/64: Implement clear_bit_unlock_is_negative_byte() powerpc/powernv: Remove unused variable in pnv_pci_sriov_disable() powerpc/kernel: Remove error message in pcibios_setup_phb_resources() powerpc/mm: Fix typo in set_pte_at() pci/hotplug/pnv-php: Disable MSI and PCI device properly pci/hotplug/pnv-php: Disable surprise hotplug capability on conflicts pci/hotplug/pnv-php: Remove WARN_ON() in pnv_php_put_slot() powerpc: Add POWER9 architected mode to cputable powerpc/perf: use is_kernel_addr macro in perf_get_misc_flags() powerpc/perf: Avoid FAB_*_MATCH checks for power9 powerpc/perf: Add restrictions to PMC5 in power9 DD1 powerpc/perf: Use Instruction Counter value ...
2017-01-25powerpc/8xx: Implement hw_breakpointChristophe Leroy
This patch implements HW breakpoint on the 8xx. The 8xx has capability to manage HW breakpoints, which is slightly different than BOOK3S: 1/ The breakpoint match doesn't trigger a DSI exception but a dedicated data breakpoint exception. 2/ The breakpoint happens after the instruction has completed, no need to single step or emulate the instruction, 3/ Matched address is not set in DAR but in BAR, 4/ DABR register doesn't exist, instead we have registers LCTRL1, LCTRL2 and CMPx registers, 5/ The match on one comparator is not on a double word but on a single word. The patch does: 1/ Prepare the dedicated registers in call to __set_dabr(). In order to emulate the double word handling of BOOK3S, comparator E is set to DABR address value and comparator F to address + 4. Then breakpoint 1 is set to match comparator E or F, 2/ Skip the singlestepping stage when compiled for CONFIG_PPC_8xx, 3/ Implement the exception. In that exception, the matched address is taken from SPRN_BAR and manage as if it was from SPRN_DAR. 4/ I/D TLB error exception routines perform a tlbie on bad TLBs. That tlbie triggers the breakpoint exception when performed on the breakpoint address. For this reason, the routine returns if the match is from one of those two tlbie. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Scott Wood <oss@buserror.net>
2017-01-24powerpc: Revert the initial stack protector supportMichael Ellerman
Unfortunately the stack protector support we merged recently only works on some toolchains. If the toolchain is built without glibc support everything works fine, but if glibc is built then it leads to a panic at boot. The solution is not rc5 material, so revert the support for now. This reverts commits: 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support") 902e06eb86cd ("powerpc/32: Change the stack protector canary value per task") Fixes: 6533b7c16ee5 ("powerpc: Initial stack protector (-fstack-protector) support") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-12-16Merge tag 'powerpc-4.10-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights include: - Support for the kexec_file_load() syscall, which is a prereq for secure and trusted boot. - Prevent kernel execution of userspace on P9 Radix (similar to SMEP/PXN). - Sort the exception tables at build time, to save time at boot, and store them as relative offsets to save space in the kernel image & memory. - Allow building the kernel with thin archives, which should allow us to build an allyesconfig once some other fixes land. - Build fixes to allow us to correctly rebuild when changing the kernel endian from big to little or vice versa. - Plumbing so that we can avoid doing a full mm TLB flush on P9 Radix. - Initial stack protector support (-fstack-protector). - Support for dumping the radix (aka. Linux) and hash page tables via debugfs. - Fix an oops in cxl coredump generation when cxl_get_fd() is used. - Freescale updates from Scott: "Highlights include 8xx hugepage support, qbman fixes/cleanup, device tree updates, and some misc cleanup." - Many and varied fixes and minor enhancements as always. Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Bartlomiej Zolnierkiewicz, Christophe Jaillet, Christophe Leroy, Denis Kirjanov, Elimar Riesebieter, Frederic Barrat, Gautham R. Shenoy, Geliang Tang, Geoff Levand, Jack Miller, Johan Hovold, Lars-Peter Clausen, Libin, Madhavan Srinivasan, Michael Neuling, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Pan Xinhui, Peter Senna Tschudin, Rashmica Gupta, Rui Teng, Russell Currey, Scott Wood, Simon Guo, Suraj Jitindar Singh, Thiago Jung Bauermann, Tobias Klauser, Vaibhav Jain" [ And thanks to Michael, who took time off from a new baby to get this pull request done. - Linus ] * tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (174 commits) powerpc/fsl/dts: add FMan node for t1042d4rdb powerpc/fsl/dts: add sg_2500_aqr105_phy4 alias on t1024rdb powerpc/fsl/dts: add QMan and BMan nodes on t1024 powerpc/fsl/dts: add QMan and BMan nodes on t1023 soc/fsl/qman: test: use DEFINE_SPINLOCK() powerpc/fsl-lbc: use DEFINE_SPINLOCK() powerpc/8xx: Implement support of hugepages powerpc: get hugetlbpage handling more generic powerpc: port 64 bits pgtable_cache to 32 bits powerpc/boot: Request no dynamic linker for boot wrapper soc/fsl/bman: Use resource_size instead of computation soc/fsl/qe: use builtin_platform_driver powerpc/fsl_pmc: use builtin_platform_driver powerpc/83xx/suspend: use builtin_platform_driver powerpc/ftrace: Fix the comments for ftrace_modify_code powerpc/perf: macros for power9 format encoding powerpc/perf: power9 raw event format encoding powerpc/perf: update attribute_group data structure powerpc/perf: factor out the event format field powerpc/mm/iommu, vfio/spapr: Put pages on VFIO container shutdown ...
2016-11-23powerpc: Initial stack protector (-fstack-protector) supportChristophe Leroy
Partialy copied from commit c743f38013aef ("ARM: initial stack protector (-fstack-protector) support") This is the very basic stuff without the changing canary upon task switch yet. Just the Kconfig option and a constant canary value initialized at boot time. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-14powerpc: Revert Load Monitor Register SupportMichael Neuling
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>
2016-11-12powerpc/oops: Fix missing pr_cont()s in instruction dumpAndrew Donnellan
Since the KERN_CONT changes, the current code in show_instructions() prints out a whole bunch of unnecessary newlines. Change occurrences of printk("\n") to pr_cont("\n"). While we're here, change all the other cases of printk(KERN_CONT ...) to pr_cont() as well. Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-12powerpc/oops: Fix missing pr_cont()s in show_regs()Michael Ellerman
Fix up our oops output by converting continuation lines to use pr_cont(). Some of these are dubious, eg. printing a continuation line which starts with a newline, but seem to work OK for now. This whole function needs a rewrite in the next release. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-12powerpc/oops: Fix missing pr_cont()s in print_msr_bits() et. al.Michael Ellerman
Since the KERN_CONT changes these are being horribly split across lines, for example: MSR: 8000000000009033 < SF,EE ,ME,IR ,DR,RI ,LE> So fix it by using pr_cont() where appropriate. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>