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2019-11-25powerpc: Avoid clang warnings around setjmp and longjmpNathan Chancellor
Commit aea447141c7e ("powerpc: Disable -Wbuiltin-requires-header when setjmp is used") disabled -Wbuiltin-requires-header because of a warning about the setjmp and longjmp declarations. r367387 in clang added another diagnostic around this, complaining that there is no jmp_buf declaration. In file included from ../arch/powerpc/xmon/xmon.c:47: ../arch/powerpc/include/asm/setjmp.h:10:13: error: declaration of built-in function 'setjmp' requires the declaration of the 'jmp_buf' type, commonly provided in the header <setjmp.h>. [-Werror,-Wincomplete-setjmp-declaration] extern long setjmp(long *); ^ ../arch/powerpc/include/asm/setjmp.h:11:13: error: declaration of built-in function 'longjmp' requires the declaration of the 'jmp_buf' type, commonly provided in the header <setjmp.h>. [-Werror,-Wincomplete-setjmp-declaration] extern void longjmp(long *, long); ^ 2 errors generated. We are not using the standard library's longjmp/setjmp implementations for obvious reasons; make this clear to clang by using -ffreestanding on these files. Cc: stable@vger.kernel.org # 4.14+ Suggested-by: Segher Boessenkool <segher@kernel.crashing.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191119045712.39633-3-natechancellor@gmail.com
2019-11-13powerpc/watchpoint: Introduce macros for watchpoint lengthRavi Bangoria
We are hadrcoding length everywhere in the watchpoint code. Introduce macros for the length and use them. Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191017093204.7511-2-ravi.bangoria@linux.ibm.com
2019-10-28powerpc/xmon: Restrict when kernel is locked downChristopher M. Riedl
Xmon should be either fully or partially disabled depending on the kernel lockdown state. Put xmon into read-only mode for lockdown=integrity and prevent user entry into xmon when lockdown=confidentiality. Xmon checks the lockdown state on every attempted entry: (1) during early xmon'ing (2) when triggered via sysrq (3) when toggled via debugfs (4) when triggered via a previously enabled breakpoint The following lockdown state transitions are handled: (1) lockdown=none -> lockdown=integrity set xmon read-only mode (2) lockdown=none -> lockdown=confidentiality clear all breakpoints, set xmon read-only mode, prevent user re-entry into xmon (3) lockdown=integrity -> lockdown=confidentiality clear all breakpoints, set xmon read-only mode, prevent user re-entry into xmon Suggested-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190907061124.1947-3-cmr@informatik.wtf
2019-10-28powerpc/xmon: Allow listing and clearing breakpoints in read-only modeChristopher M. Riedl
Read-only mode should not prevent listing and clearing any active breakpoints. Tested-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190907061124.1947-2-cmr@informatik.wtf
2019-09-14powerpc/xmon: Improve output of XIVE interruptsCédric Le Goater
When looping on the list of interrupts, add the current value of the PQ bits with a load on the ESB page. This has the side effect of faulting the ESB page of all interrupts. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190910081850.26038-2-clg@kaod.org
2019-08-19powerpc/xmon: Add a dump of all XIVE interruptsCédric Le Goater
Modify the xmon 'dxi' command to query all interrupts if no IRQ number is specified. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190814154754.23682-4-clg@kaod.org
2019-08-19powerpc/xive: Fix dump of XIVE interrupt under pseriesCédric Le Goater
The xmon 'dxi' command calls OPAL to query the XIVE configuration of a interrupt. This can only be done on baremetal (PowerNV) and it will crash a pseries machine. Introduce a new XIVE get_irq_config() operation which implements a different query depending on the platform, PowerNV or pseries, and modify xmon to use a top level wrapper. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190814154754.23682-3-clg@kaod.org
2019-08-19powerpc/xmon: Check for HV mode when dumping XIVE info from OPALCédric Le Goater
Currently, the xmon 'dx' command calls OPAL to dump the XIVE state in the OPAL logs and also outputs some of the fields of the internal XIVE structures in Linux. The OPAL calls can only be done on baremetal (PowerNV) and they crash a pseries machine. Fix by checking the hypervisor feature of the CPU. Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190814154754.23682-2-clg@kaod.org
2019-07-13Merge tag 'powerpc-5.3-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver, as well as some other functions only used by drivers that haven't (yet?) made it upstream. - A fix for a bug in our handling of hardware watchpoints (eg. perf record -e mem: ...) which could lead to register corruption and kernel crashes. - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for vmalloc when using the Radix MMU. - A large but incremental rewrite of our exception handling code to use gas macros rather than multiple levels of nested CPP macros. And the usual small fixes, cleanups and improvements. Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz, Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj Jitindar Singh, Thiago Jung Bauermann, YueHaibing" * tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits) powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state. powerpc/eeh: Handle hugepages in ioremap space ocxl: Update for AFU descriptor template version 1.1 powerpc/boot: pass CONFIG options in a simpler and more robust way powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h powerpc/irq: Don't WARN continuously in arch_local_irq_restore() powerpc/module64: Use symbolic instructions names. powerpc/module32: Use symbolic instructions names. powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h powerpc/module64: Fix comment in R_PPC64_ENTRY handling powerpc/boot: Add lzo support for uImage powerpc/boot: Add lzma support for uImage powerpc/boot: don't force gzipped uImage powerpc/8xx: Add microcode patch to move SMC parameter RAM. powerpc/8xx: Use IO accessors in microcode programming. powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c powerpc/8xx: refactor programming of microcode CPM params. powerpc/8xx: refactor printing of microcode patch name. powerpc/8xx: Refactor microcode write powerpc/8xx: refactor writing of CPM microcode arrays ...
2019-07-05powerpc/book3s: Use config independent helpers for page table walkAneesh Kumar K.V
Even when we have HugeTLB and THP disabled, kernel linear map can still be mapped with hugepages. This is only an issue with radix translation because hash MMU doesn't map kernel linear range in linux page table and other kernel map areas are not mapped using hugepage. Add config independent helpers and put WARN_ON() when we don't expect things to be mapped via hugepages. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-02powerpc/64s/exception: remove bad stack branchNicholas Piggin
The bad stack test in interrupt handlers has a few problems. For performance it is taken in the common case, which is a fetch bubble and a waste of i-cache. For code development and maintainence, it requires yet another stack frame setup routine, and that constrains all exception handlers to follow the same register save pattern which inhibits future optimisation. Remove the test/branch and replace it with a trap. Teach the program check handler to use the emergency stack for this case. This does not result in quite so nice a message, however the SRR0 and SRR1 of the crashed interrupt can be seen in r11 and r12, as is the original r1 (adjusted by INT_FRAME_SIZE). These are the most important parts to debugging the issue. The original r9-12 and cr0 is lost, which is the main downside. kernel BUG at linux/arch/powerpc/kernel/exceptions-64s.S:847! Oops: Exception in kernel mode, sig: 5 [#1] BE SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted NIP: c000000000009108 LR: c000000000cadbcc CTR: c0000000000090f0 REGS: c0000000fffcbd70 TRAP: 0700 Not tainted MSR: 9000000000021032 <SF,HV,ME,IR,DR,RI> CR: 28222448 XER: 20040000 CFAR: c000000000009100 IRQMASK: 0 GPR00: 000000000000003d fffffffffffffd00 c0000000018cfb00 c0000000f02b3166 GPR04: fffffffffffffffd 0000000000000007 fffffffffffffffb 0000000000000030 GPR08: 0000000000000037 0000000028222448 0000000000000000 c000000000ca8de0 GPR12: 9000000002009032 c000000001ae0000 c000000000010a00 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: c0000000f00322c0 c000000000f85200 0000000000000004 ffffffffffffffff GPR24: fffffffffffffffe 0000000000000000 0000000000000000 000000000000000a GPR28: 0000000000000000 0000000000000000 c0000000f02b391c c0000000f02b3167 NIP [c000000000009108] decrementer_common+0x18/0x160 LR [c000000000cadbcc] .vsnprintf+0x3ec/0x4f0 Call Trace: Instruction dump: 996d098a 994d098b 38610070 480246ed 48005518 60000000 38200000 718a4000 7c2a0b78 3821fd00 41c20008 e82d0970 <0981fd00> f92101a0 f9610170 f9810178 Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-01powerpc/xmon: Fix disabling tracing while in xmonNaveen N. Rao
Commit ed49f7fd6438d ("powerpc/xmon: Disable tracing when entering xmon") added code to disable recording trace entries while in xmon. The commit introduced a variable 'tracing_enabled' to record if tracing was enabled on xmon entry, and used this to conditionally enable tracing during exit from xmon. However, we are not checking the value of 'fromipi' variable in xmon_core() when setting 'tracing_enabled'. Due to this, when secondary cpus enter xmon, they will see tracing as being disabled already and tracing won't be re-enabled on exit. Fix the same. Fixes: ed49f7fd6438d ("powerpc/xmon: Disable tracing when entering xmon") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 76Thomas Gleixner
Based on 1 normalized pattern(s): gdb gas and the gnu binutils are free software you can redistribute them and or modify them under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version gdb gas and the gnu binutils are distributed in the hope that they will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this file see the file copying if not write to the free software foundation 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 2 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520075210.666183009@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 1Thomas Gleixner
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option [no]_[pad]_[ctrl] any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 176 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154040.652910950@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-10Merge tag 'powerpc-5.2-1' of ↵Linus Torvalds
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Slightly delayed due to the issue with printk() calling probe_kernel_read() interacting with our new user access prevention stuff, but all fixed now. The only out-of-area changes are the addition of a cpuhp_state, small additions to Documentation and MAINTAINERS updates. Highlights: - Support for Kernel Userspace Access/Execution Prevention (like SMAP/SMEP/PAN/PXN) on some 64-bit and 32-bit CPUs. This prevents the kernel from accidentally accessing userspace outside copy_to/from_user(), or ever executing userspace. - KASAN support on 32-bit. - Rework of where we map the kernel, vmalloc, etc. on 64-bit hash to use the same address ranges we use with the Radix MMU. - A rewrite into C of large parts of our idle handling code for 64-bit Book3S (ie. power8 & power9). - A fast path entry for syscalls on 32-bit CPUs, for a 12-17% speedup in the null_syscall benchmark. - On 64-bit bare metal we have support for recovering from errors with the time base (our clocksource), however if that fails currently we hang in __delay() and never crash. We now have support for detecting that case and short circuiting __delay() so we at least panic() and reboot. - Add support for optionally enabling the DAWR on Power9, which had to be disabled by default due to a hardware erratum. This has the effect of enabling hardware breakpoints for GDB, the downside is a badly behaved program could crash the machine by pointing the DAWR at cache inhibited memory. This is opt-in obviously. - xmon, our crash handler, gets support for a read only mode where operations that could change memory or otherwise disturb the system are disabled. Plus many clean-ups, reworks and minor fixes etc. Thanks to: Christophe Leroy, Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Ben Hutchings, Bo YU, Breno Leitao, Cédric Le Goater, Christopher M. Riedl, Christoph Hellwig, Colin Ian King, David Gibson, Ganesh Goudar, Gautham R. Shenoy, George Spelvin, Greg Kroah-Hartman, Greg Kurz, Horia Geantă, Jagadeesh Pagadala, Joel Stanley, Joe Perches, Julia Lawall, Laurentiu Tudor, Laurent Vivier, Lukas Bulwahn, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael Neuling, Mukesh Ojha, Nathan Fontenot, Nathan Lynch, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Peng Hao, Qian Cai, Ravi Bangoria, Rick Lindsley, Russell Currey, Sachin Sant, Stewart Smith, Sukadev Bhattiprolu, Thomas Huth, Tobin C. Harding, Tyrel Datwyler, Valentin Schneider, Wei Yongjun, Wen Yang, YueHaibing" * tag 'powerpc-5.2-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (205 commits) powerpc/64s: Use early_mmu_has_feature() in set_kuap() powerpc/book3s/64: check for NULL pointer in pgd_alloc() powerpc/mm: Fix hugetlb page initialization ocxl: Fix return value check in afu_ioctl() powerpc/mm: fix section mismatch for setup_kup() powerpc/mm: fix redundant inclusion of pgtable-frag.o in Makefile powerpc/mm: Fix makefile for KASAN powerpc/kasan: add missing/lost Makefile selftests/powerpc: Add a signal fuzzer selftest powerpc/booke64: set RI in default MSR ocxl: Provide global MMIO accessors for external drivers ocxl: move event_fd handling to frontend ocxl: afu_irq only deals with IRQ IDs, not offsets ocxl: Allow external drivers to use OpenCAPI contexts ocxl: Create a clear delineation between ocxl backend & frontend ocxl: Don't pass pci_dev around ocxl: Split pci.c ocxl: Remove some unused exported symbols ocxl: Remove superfluous 'extern' from headers ocxl: read_pasid never returns an error, so make it void ...
2019-05-03powerpc/xmon: add read-only modeChristopher M. Riedl
Operations which write to memory and special purpose registers should be restricted on systems with integrity guarantees (such as Secure Boot) and, optionally, to avoid self-destructive behaviors. Add a config option, XMON_DEFAULT_RO_MODE, to set default xmon behavior. The kernel cmdline options xmon=ro and xmon=rw override this default. The following xmon operations are affected: memops: disable memmove disable memset disable memzcan memex: no-op'd mwrite super_regs: no-op'd write_spr bpt_cmds: disable proc_call: disable Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf> Reviewed-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03powerpc: disable KASAN instrumentation on early/critical files.Christophe Leroy
All files containing functions run before kasan_early_init() is called must have KASAN instrumentation disabled. For those file, branch profiling also have to be disabled otherwise each if () generates a call to ftrace_likely_update(). Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-30powerpc/64s: Reimplement book3s idle code in CNicholas Piggin
Reimplement Book3S idle code in C, moving POWER7/8/9 implementation speific HV idle code to the powernv platform code. Book3S assembly stubs are kept in common code and used only to save the stack frame and non-volatile GPRs before executing architected idle instructions, and restoring the stack and reloading GPRs then returning to C after waking from idle. The complex logic dealing with threads and subcores, locking, SPRs, HMIs, timebase resync, etc., is all done in C which makes it more maintainable. This is not a strict translation to C code, there are some significant differences: - Idle wakeup no longer uses the ->cpu_restore call to reinit SPRs, but saves and restores them itself. - The optimisation where EC=ESL=0 idle modes did not have to save GPRs or change MSR is restored, because it's now simple to do. ESL=1 sleeps that do not lose GPRs can use this optimization too. - KVM secondary entry and cede is now more of a call/return style rather than branchy. nap_state_lost is not required because KVM always returns via NVGPR restoring path. - KVM secondary wakeup from offline sequence is moved entirely into the offline wakeup, which avoids a hwsync in the normal idle wakeup path. Performance measured with context switch ping-pong on different threads or cores, is possibly improved a small amount, 1-3% depending on stop state and core vs thread test for shallow states. Deep states it's in the noise compared with other latencies. KVM improvements: - Idle sleepers now always return to caller rather than branch out to KVM first. - This allows optimisations like very fast return to caller when no state has been lost. - KVM no longer requires nap_state_lost because it controls NVGPR save/restore itself on the way in and out. - The heavy idle wakeup KVM request check can be moved out of the normal host idle code and into the not-performance-critical offline code. - KVM nap code now returns from where it is called, which makes the flow a bit easier to follow. Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Squash the KVM changes in] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-08powerpc/mmiowb: Hook up mmwiob() implementation to asm-generic codeWill Deacon
In a bid to kill off explicit mmiowb() usage in driver code, hook up the asm-generic mmiowb() tracking code but provide a definition of arch_mmiowb_state() so that the tracking data can remain in the paca as it does at present This replaces the existing (flawed) implementation. Acked-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-02-26powerpc/xmon: Fix opcode being uninitialized in print_insn_powerpcNathan Chancellor
When building with -Wsometimes-uninitialized, Clang warns: arch/powerpc/xmon/ppc-dis.c:157:7: warning: variable 'opcode' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] if (cpu_has_feature(CPU_FTRS_POWER9)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/xmon/ppc-dis.c:167:7: note: uninitialized use occurs here if (opcode == NULL) ^~~~~~ arch/powerpc/xmon/ppc-dis.c:157:3: note: remove the 'if' if its condition is always true if (cpu_has_feature(CPU_FTRS_POWER9)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/xmon/ppc-dis.c:132:38: note: initialize the variable 'opcode' to silence this warning const struct powerpc_opcode *opcode; ^ = NULL 1 warning generated. This warning seems to make no sense on the surface because opcode is set to NULL right below this statement. However, there is a comma instead of semicolon to end the dialect assignment, meaning that the opcode assignment only happens in the if statement. Properly terminate that line so that Clang no longer warns. Fixes: 5b102782c7f4 ("powerpc/xmon: Enable disassembly files (compilation changes)") Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23powerpc: Only use task_struct 'cpu' field on SMPChristophe Leroy
When moving to CONFIG_THREAD_INFO_IN_TASK, the thread_info 'cpu' field gets moved into task_struct and only defined when CONFIG_SMP is set. This patch ensures that TI_CPU is only used when CONFIG_SMP is set and that task_struct 'cpu' field is not used directly out of SMP code. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23powerpc: Enable kcovAndrew Donnellan
kcov provides kernel coverage data that's useful for fuzzing tools like syzkaller. Wire up kcov support on powerpc. Disable kcov instrumentation on the same files where we currently disable gcov and UBSan instrumentation, plus some additional exclusions which appear necessary to boot on book3e machines. Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Daniel Axtens <dja@axtens.net> # e6500 Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19powerpc/xmon: fix dump_segments()Christophe Leroy
mfsrin() takes segment num from bits 31-28 (IBM bits 0-3). Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Clarify bit numbering] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04powerpc: annotate implicit fall throughsStephen Rothwell
There is a plan to build the kernel with -Wimplicit-fallthrough and these places in the code produced warnings, but because we build arch/powerpc with -Werror, they became errors. Fix them up. This patch produces no change in behaviour, but should be reviewed in case these are actually bugs not intentional fallthoughs. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04powerpc/xmon: Fix invocation inside lock regionBreno Leitao
Currently xmon needs to get devtree_lock (through rtas_token()) during its invocation (at crash time). If there is a crash while devtree_lock is being held, then xmon tries to get the lock but spins forever and never get into the interactive debugger, as in the following case: int *ptr = NULL; raw_spin_lock_irqsave(&devtree_lock, flags); *ptr = 0xdeadbeef; This patch avoids calling rtas_token(), thus trying to get the same lock, at crash time. This new mechanism proposes getting the token at initialization time (xmon_init()) and just consuming it at crash time. This would allow xmon to be possible invoked independent of devtree_lock being held or not. Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-26powerpc: change CONFIG_PPC_STD_MMU to CONFIG_PPC_BOOK3SChristophe Leroy
Today we have: config PPC_BOOK3S def_bool y depends on PPC_BOOK3S_32 || PPC_BOOK3S_64 config PPC_STD_MMU def_bool y depends on PPC_BOOK3S PPC_STD_MMU is therefore redundant with PPC_BOOK3S. Lets remove it. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-26powerpc: change CONFIG_PPC_STD_MMU_32 to CONFIG_PPC_BOOK3S_32Christophe Leroy
Today we have: config PPC_BOOK3S_32 bool "512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx" [depends on PPC32 within a choice] config PPC_BOOK3S def_bool y depends on PPC_BOOK3S_32 || PPC_BOOK3S_64 config PPC_STD_MMU def_bool y depends on PPC_BOOK3S config PPC_STD_MMU_32 def_bool y depends on PPC_STD_MMU && PPC32 PPC_STD_MMU_32 is therefore redundant with PPC_BOOK3S_32. In order to make the code clearer, lets use preferably PPC_BOOK3S_32. This will allow to remove CONFIG_PPC_STD_MMU_32 in a later patch. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-25powerpc/xmon: Define static functionsBreno Leitao
Currently sparse is complaining about three issues on the xmon code. Two storage classes issues and a dereferencing a 'noderef' pointer. These are the warnings: arch/powerpc/xmon/xmon.c:2783:1: warning: symbol 'dump_log_buf' was not declared. Should it be static? arch/powerpc/xmon/xmon.c:2989:6: warning: symbol 'format_pte' was not declared. Should it be static? arch/powerpc/xmon/xmon.c:2983:30: warning: dereference of noderef expression This patch fixes all of them, turning both functions static and dereferencing a pointer calling rcu_dereference() instead of a straightforward dereference. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-31powerpc/xmon: Relax frame size for clangJoel Stanley
When building with clang (8 trunk, 7.0 release) the frame size limit is hit: arch/powerpc/xmon/xmon.c:452:12: warning: stack frame size of 2576 bytes in function 'xmon_core' [-Wframe-larger-than=] Some investigation by Naveen indicates this is due to clang saving the addresses to printf format strings on the stack. While this issue is investigated, bump up the frame size limit for xmon when building with clang. Link: https://github.com/ClangBuiltLinux/linux/issues/252 Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-20powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64Christophe Leroy
scaled cputime is only meaningfull when the processor has SPURR and/or PURR, which means only on PPC64. Removing it on PPC32 significantly reduces the size of vtime_account_system() and vtime_account_idle() on an 8xx: Before: 00000000 l F .text 000000a8 vtime_delta 00000280 g F .text 0000010c vtime_account_system 0000038c g F .text 00000048 vtime_account_idle After: (vtime_delta gets inlined inside the two functions) 000001d8 g F .text 000000a0 vtime_account_system 00000278 g F .text 00000038 vtime_account_idle In terms of performance, we also get approximatly 7% improvement on task switch. The following small benchmark app is run with perf stat: void *thread(void *arg) { int i; for (i = 0; i < atoi((char*)arg); i++) pthread_yield(); } int main(int argc, char **argv) { pthread_t th1, th2; pthread_create(&th1, NULL, thread, argv[1]); pthread_create(&th2, NULL, thread, argv[1]); pthread_join(th1, NULL); pthread_join(th2, NULL); return 0; } Before the patch: Performance counter stats for 'chrt -f 98 ./sched 100000' (50 runs): 8228.476465 task-clock (msec) # 0.954 CPUs utilized ( +- 0.23% ) 200004 context-switches # 0.024 M/sec ( +- 0.00% ) After the patch: Performance counter stats for 'chrt -f 98 ./sched 100000' (50 runs): 7649.070444 task-clock (msec) # 0.955 CPUs utilized ( +- 0.27% ) 200004 context-switches # 0.026 M/sec ( +- 0.00% ) Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-19powerpc: Add -Werror at arch/powerpc levelMichael Ellerman
Back when I added -Werror in commit ba55bd74360e ("powerpc: Add configurable -Werror for arch/powerpc") I did it by adding it to most of the arch Makefiles. At the time we excluded math-emu, because apparently it didn't build cleanly. But that seems to have been fixed somewhere in the interim. So move the -Werror addition to the top-level of the arch, this saves us from repeating it in every Makefile and means we won't forget to add it to any new sub-dirs. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14powerpc/64s/hash: Add SLB allocation status bitmapsNicholas Piggin
Add 32-entry bitmaps to track the allocation status of the first 32 SLB entries, and whether they are user or kernel entries. These are used to allocate free SLB entries first, before resorting to the round robin allocator. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14powerpc/mm: use pte helpers in generic codeChristophe Leroy
Get rid of platform specific _PAGE_XXXX in powerpc common code and use helpers instead. mm/dump_linuxpagetables.c will be handled separately Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-13powerpc/xmon: Show the stack protector canary in xmonMichael Ellerman
This is helpful for debugging stack protector crashes. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-13powerpc: Disable -Wbuiltin-requires-header when setjmp is usedJoel Stanley
The powerpc kernel uses setjmp which causes a warning when building with clang: In file included from arch/powerpc/xmon/xmon.c:51: ./arch/powerpc/include/asm/setjmp.h:15:13: error: declaration of built-in function 'setjmp' requires inclusion of the header <setjmp.h> [-Werror,-Wbuiltin-requires-header] extern long setjmp(long *); ^ ./arch/powerpc/include/asm/setjmp.h:16:13: error: declaration of built-in function 'longjmp' requires inclusion of the header <setjmp.h> [-Werror,-Wbuiltin-requires-header] extern void longjmp(long *, long); ^ This *is* the header and we're not using the built-in setjump but rather the one in arch/powerpc/kernel/misc.S. As the compiler warning does not make sense, it for the files where setjmp is used. Signed-off-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> [mpe: Move subdir-ccflags in xmon/Makefile to not clobber -Werror] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-03Revert "convert SLB miss handlers to C" and subsequent commitsMichael Ellerman
This reverts commits: 5e46e29e6a97 ("powerpc/64s/hash: convert SLB miss handlers to C") 8fed04d0f6ae ("powerpc/64s/hash: remove user SLB data from the paca") 655deecf67b2 ("powerpc/64s/hash: SLB allocation status bitmaps") 2e1626744e8d ("powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup") 89ca4e126a3f ("powerpc/64s/hash: Add a SLB preload cache") This series had a few bugs, and the fixes are not all trivial. So revert most of it for now. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19powerpc: consolidate -mno-sched-epilog into FTRACE flagsNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19powerpc/64s: xmon do not dump hash fields when using radix modeNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19powerpc/64s/hash: SLB allocation status bitmapsNicholas Piggin
Add 32-entry bitmaps to track the allocation status of the first 32 SLB entries, and whether they are user or kernel entries. These are used to allocate free SLB entries first, before resorting to the round robin allocator. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19powerpc/64s/hash: Use POWER9 SLBIA IH=3 variant in switch_slbNicholas Piggin
POWER9 introduces SLBIA IH=3, which invalidates all SLB entries and associated lookaside information that have a class value of 1, which Linux assigns to user addresses. This matches what switch_slb wants, and allows a simple fast implementation that avoids the slb_cache complexity. As a side-effect, the POWER5 < DD2.1 SLB invalidation workaround is also avoided on POWER9. Process context switching rate is improved about 2.2% for a small process that hits the slb cache which is the best case for the current code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-13Merge branch 'fixes' into nextMichael Ellerman
Merge our fixes branch from the 4.18 cycle to resolve some minor conflicts.
2018-08-10powerpc/xmon: Add address lookup for percpu symbolsBoqun Feng
Currently, in xmon, there is no obvious way to get an address for a percpu symbol for a particular cpu. Having such an ability would be good for debugging the system when percpu variables got involved. Therefore, this patch introduces a new xmon command "lp" to lookup the address for percpu symbols. Usage of "lp" is similar to "ls", except that we could add a cpu number to choose the variable of which cpu we want to lookup. If no cpu number is given, lookup for current cpu. Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-30powerpc: move ASM_CONST and stringify_in_c() into asm-const.hChristophe Leroy
This patch moves ASM_CONST() and stringify_in_c() into dedicated asm-const.h, then cleans all related inclusions. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: asm-compat.h should include asm-const.h] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-19Merge branch 'topic/ppc-kvm' into nextMichael Ellerman
Merge in some commits we're sharing with the KVM tree. I manually propagated the change from commit d3d4ffaae439 ("powerpc/powernv/ioda2: Reduce upper limit for DMA window size") into pci-ioda-tce.c. Conflicts: arch/powerpc/include/asm/cputable.h arch/powerpc/platforms/powernv/pci-ioda.c arch/powerpc/platforms/powernv/pci.h
2018-07-17powerpc/xmon: Fix disassembly since printf changesMichael Ellerman
The recent change to add printf annotations to xmon inadvertently made the disassembly output ugly, eg: c00000002001e058 7ee00026 mfcr r23 c00000002001e05c fffffffffae101a0 std r23,416(r1) c00000002001e060 fffffffff8230000 std r1,0(r3) The problem being that negative 32-bit values are being displayed in full 64-bits. The printf conversion was actually correct, we are passing unsigned long so it should use "lx". But powerpc instructions are only 4 bytes and the code only reads 4 bytes, so inst should really just be unsigned int, and that also fixes the printing to look the way we want: c00000002001e058 7ee00026 mfcr r23 c00000002001e05c fae101a0 std r23,416(r1) c00000002001e060 f8230000 std r1,0(r3) Fixes: e70d8f55268b ("powerpc/xmon: Add __printf annotation to xmon_printf()") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16powerpc/64s: Remove POWER9 DD1 supportNicholas Piggin
POWER9 DD1 was never a product. It is no longer supported by upstream firmware, and it is not effectively supported in Linux due to lack of testing. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> [mpe: Remove arch_make_huge_pte() entirely] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-02powerpc: xmon: use ktime_get_coarse_boottime64Arnd Bergmann
get_monotonic_boottime() is deprecated, and may not be safe to call in every context, as it has to read a hardware clocksource. This changes xmon to print the time using ktime_get_coarse_boottime64() instead, which avoids the old timespec type and the HW access. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03powerpc/64: Save stack pointer when we hard disable interruptsMichael Ellerman
A CPU that gets stuck with interrupts hard disable can be difficult to debug, as on some platforms we have no way to interrupt the CPU to find out what it's doing. A stop-gap is to have the CPU save it's stack pointer (r1) in its paca when it hard disables interrupts. That way if we can't interrupt it, we can at least trace the stack based on where it last disabled interrupts. In some cases that will be total junk, but the stack trace code should handle that. In the simple case of a CPU that disable interrupts and then gets stuck in a loop, the stack trace should be informative. We could clear the saved stack pointer when we enable interrupts, but that loses information which could be useful if we have nothing else to go on. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Nicholas Piggin <npiggin@gmail.com>