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2020-04-01Merge branch 'for-5.7/core' into for-linusJiri Kosina
- device-specific (ITE 8595) fix from Hans de Goede
2020-04-01Merge branch 'for-5.7/appleir' into for-linusJiri Kosina
- small code cleanups in hid-appleir from Lucas Tanure
2020-04-01Merge branch 'for-5.6/upstream-fixes' into for-linusJiri Kosina
- probe fix for Logitech-G* devices from Hans de Goede - error handling imrovement in hid-rmi from Christophe JAILLET
2020-04-01Merge tag 'irqchip-fixes-5.7-1' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core Pull irqchip fixes from Marc Zygnier: - Partially revert Xilinx changes that break PPC systems
2020-04-01PM: sleep: core: Drop racy and redundant checks from device_prepare()Rafael J. Wysocki
Alan Stern points out that the WARN_ON() check in device_prepare() is racy (because the PM-runtime API can be disabled briefly for any device at any time and system suspend can start at any time too) and the pm_runtime_suspended() check in the computation of the direct_complete flag value is redundant (because it will be repeated later anyway). Drop both these checks accordingly. Reported-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-01PM: hibernate: Propagate the return value of hibernation_restore()Dexuan Cui
If hibernation_restore() fails, the 'error' should not be zero. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-01ACPI: video: Use native backlight on Acer Aspire 5783zHans de Goede
The Acer Aspire 5783z shipped with Windows 7 and as such does not trigger our "win8 ready" heuristic for prefering the native backlight interface. Still ACPI backlight control doesn't work on this model, where as the native (intel_video) backlight interface does work. Add a quirk to force using native backlight control on this model. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-01ACPI: video: Docs update for "acpi_backlight" kernel parameter optionsRandy Dunlap
Update the Documentation for "acpi_backlight" by adding 2 new options (native and none). Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-01Revert "irqchip/xilinx: Enable generic irq multi handler"Marc Zyngier
This reverts commit a0789993bf8266e62fea6b4613945ba081c71e7d, which breaks a number of PPC platforms. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/44b64be7-9240-fd52-af90-e0245220f38b@xilinx.com
2020-04-01Revert "irqchip/xilinx: Do not call irq_set_default_host()"Marc Zyngier
This reverts commit 9c2d4f525c002591f4e0c14a37663663aaba1656, which breaks a number of PPC platforms. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/44b64be7-9240-fd52-af90-e0245220f38b@xilinx.com
2020-04-01Revert "driver core: platform: Initialize dma_parms for platform devices"Greg Kroah-Hartman
This reverts commit 7c8978c0837d40c302f5e90d24c298d9ca9fc097, a new version will come in the next release cycle. Cc: <stable@vger.kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Ludovic Barre <ludovic.barre@st.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-01Revert "amba: Initialize dma_parms for amba devices"Greg Kroah-Hartman
This reverts commit 5caf6102e32ead7ed5d21b5309c1a4a7d70e6a9f. It still needs some more work and that will happen for the next release cycle, not this one. Cc: <stable@vger.kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Ludovic Barre <ludovic.barre@st.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-01gpio: export of_pinctrl_get to modulesStephen Rothwell
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/r/20200401151904.6948af20@canb.auug.org.au Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-04-01powerpc: Make setjmp/longjmp signature standardClement Courbet
Declaring setjmp()/longjmp() as taking longs makes the signature non-standard, and makes clang complain. In the past, this has been worked around by adding -ffreestanding to the compile flags. The implementation looks like it only ever propagates the value (in longjmp) or sets it to 1 (in setjmp), and we only call longjmp with integer parameters. This allows removing -ffreestanding from the compilation flags. Fixes: c9029ef9c957 ("powerpc: Avoid clang warnings around setjmp and longjmp") Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Clement Courbet <courbet@google.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200330080400.124803-1-courbet@google.com
2020-04-01powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_typeLeonardo Bras
Before checking for cpu_type == NULL, this same copy happens, so doing it here will just write the same value to the t->oprofile_type again. Remove the repeated copy, as it is unnecessary. Signed-off-by: Leonardo Bras <leonardo@linux.ibm.com> Reviewed-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200215053637.280880-1-leonardo@linux.ibm.com
2020-04-01powerpc: Suppress .eh_frame generationNaveen N. Rao
GCC v8 defaults to enabling -fasynchronous-unwind-tables due to https://gcc.gnu.org/r259298, which results in .eh_frame section being generated. This results in additional disk usage by the build, as well as the kernel modules. Since the kernel has no use for this, this section is discarded. Add -fno-asynchronous-unwind-tables to KBUILD_CFLAGS to suppress generation of .eh_frame section. Note that our VDSOs need .eh_frame, but are not affected by this change since our VDSO code are all in assembly. Reported-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1ed7cd84a7d1a3180b30c0c60e70eed8bb8b40c3.1583415544.git.naveen.n.rao@linux.vnet.ibm.com
2020-04-01powerpc: Drop -fno-dwarf2-cfi-asmNaveen N. Rao
The original commit/discussion adding -fno-dwarf2-cfi-asm refers to R_PPC64_REL32 relocations not being handled by our module loader: http://lkml.kernel.org/r/20090224065112.GA6690@bombadil.infradead.org However, that is now handled thanks to commit 9f751b82b491d ("powerpc/module: Add support for R_PPC64_REL32 relocations"). So, drop this flag from our Makefile. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/9b22a064de6eb1301d92177eb3a38559df7005d3.1583415544.git.naveen.n.rao@linux.vnet.ibm.com
2020-04-01powerpc/32: drop unused ISA_DMA_THRESHOLDMike Rapoport
The ISA_DMA_THRESHOLD variable is set by several platforms but never referenced. Remove it. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191125092033.20014-1-rppt@kernel.org
2020-04-01powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfacesShilpasri G Bhat
Commit bf9571550f52 ("powerpc/powernv: Add support to clear sensor groups data") added a mechanism to clear sensor-group data via a sysfs interface. However, the ABI for that interface has not been documented. This patch documents the ABI for the sysfs interface for sensor-groups and clearing the sensor-groups. This patch was originally sent by Shilpasri G Bhat on the mailing list: https://lkml.org/lkml/2018/8/1/85 Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com> Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1574776274-22355-1-git-send-email-ego@linux.vnet.ibm.com
2020-04-01selftests/powerpc: Fix try-run when source tree is not writableMichael Ellerman
We added a usage of try-run to pmu/ebb/Makefile to detect if the toolchain supported the -no-pie option. This fails if we build out-of-tree and the source tree is not writable, as try-run tries to write its temporary files to the current directory. That leads to the -no-pie option being silently dropped, which leads to broken executables with some toolchains. If we remove the redirect to /dev/null in try-run, we see the error: make[3]: Entering directory '/linux/tools/testing/selftests/powerpc/pmu/ebb' /usr/bin/ld: cannot open output file .54.tmp: Read-only file system collect2: error: ld returned 1 exit status make[3]: Nothing to be done for 'all'. And looking with strace we see it's trying to use a file that's in the source tree: lstat("/linux/tools/testing/selftests/powerpc/pmu/ebb/.54.tmp", 0x7ffffc0f83c8) We can fix it by setting TMPOUT to point to the $(OUTPUT) directory, and we can verify with strace it's now trying to write to the output directory: lstat("/output/kselftest/powerpc/pmu/ebb/.54.tmp", 0x7fffd1bf6bf8) And also see that the -no-pie option is now correctly detected. Fixes: 0695f8bca93e ("selftests/powerpc: Handle Makefile for unrecognized option") Cc: stable@vger.kernel.org # v5.5+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200327095319.2347641-1-mpe@ellerman.id.au
2020-04-01powerpc/vmlinux.lds: Explicitly retain .gnu.hashMichael Ellerman
Relocatable kernel builds produce a warning about .gnu.hash being an orphan section: ld: warning: orphan section `.gnu.hash' from `linker stubs' being placed in section `.gnu.hash' If we try to discard it the build fails: ld -EL -m elf64lppc -pie --orphan-handling=warn --build-id -o .tmp_vmlinux1 -T ./arch/powerpc/kernel/vmlinux.lds --whole-archive arch/powerpc/kernel/head_64.o arch/powerpc/kernel/entry_64.o ... sound/built-in.a net/built-in.a virt/built-in.a --no-whole-archive --start-group lib/lib.a --end-group ld: could not find section .gnu.hash So add an entry to explicitly retain it, as we do for .hash. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200227045933.22967-1-mpe@ellerman.id.au
2020-04-01powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.cChristophe Leroy
ptrace_triggered() is declared in asm/hw_breakpoint.h and only needed when CONFIG_HW_BREAKPOINT is set, so move it into hw_breakpoint.c Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/8402c516023da1371953a65af7df2008758ea0c4.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: create ppc_gethwdinfo()Christophe Leroy
Create ippc_gethwdinfo() to handle PPC_PTRACE_GETHWDBGINFO and reduce ifdef mess Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/82fefcc1ec75b96cece792878217a5d85ecda0c2.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: create ptrace_get_debugreg()Christophe Leroy
Create ptrace_get_debugreg() to handle PTRACE_GET_DEBUGREG and reduce ifdef mess Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/c1482c41a39cc216f4073a51070d8680f52d5054.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: split out ADV_DEBUG_REGS related functions.Christophe Leroy
Move ADV_DEBUG_REGS functions out of ptrace.c, into ptrace-adv.c and ptrace-noadv.c Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> [mpe: Squash in fixup patch from Christophe] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/e2bd7d275bd5933d848aad4fee3ca652a14d039b.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: move register viewing functions out of ptrace.cChristophe Leroy
Create a dedicated ptrace-view.c file. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/bfd8c3ed57c9057e4a5d3816737b5ee98c6f7e43.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: split out TRANSACTIONAL_MEM related functions.Christophe Leroy
Move TRANSACTIONAL_MEM functions out of ptrace.c, into ptrace-tm.c Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/2d0ef3bb2610c0344bd42252c7134f429818c000.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: split out SPE related functions.Christophe Leroy
Move CONFIG_SPE functions out of ptrace.c, into ptrace-spe.c Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/0f17a331760310b5562fae3791cdd3cf9c64237b.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: split out ALTIVEC related functions.Christophe Leroy
Move CONFIG_ALTIVEC functions out of ptrace.c, into ptrace-altivec.c Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/35dae891d01c817fca0fd6ab406a3a2c7bf07f60.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: split out VSX related functions.Christophe Leroy
Move CONFIG_VSX functions out of ptrace.c, into ptrace-vsx.c and ptrace-novsx.c Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/dc8e20c8c95b7e83add0c6dd48f9470628896c5c.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSETChristophe Leroy
PARAMETER_SAVE_AREA_OFFSET is not used, drop it. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/6dac2b49207647f75cbf0e6771a545e691f0fd93.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64Christophe Leroy
Drop a bunch of #ifdefs CONFIG_PPC64 that are not vital. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/af38b87a7e1e3efe4f9b664eaeb029e6e7d69fdb.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/ptrace: remove unused header includesChristophe Leroy
Remove unused header includes in ptrace.c and ptrace32.c Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/6276df0be87a4329c2bb46b3b0f02059ae9e70e6.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc: Move ptrace into a subdirectory.Christophe Leroy
In order to allow splitting of ptrace depending on the different CONFIG_ options, create a subdirectory dedicated to ptrace and move ptrace.c and ptrace32.c into it. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/9ebcbe37834e9d447dd97f4381084795a673260c.1582848567.git.christophe.leroy@c-s.fr
2020-04-01powerpc/64/syscall: Reconcile interruptsNicholas Piggin
This reconciles interrupts in the system call case like all other interrupts. This allows system_call_common to be shared with the scv system call implementation in a subsequent patch. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-31-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Remove lite interrupt returnNicholas Piggin
Regular interrupt return restores NVGPRS whereas lite returns do not. This is clumsy: most interrupts can return without restoring NVGPRS in most of the time, but there are special cases that require it (when registers have been modified by the kernel). So change interrupt return to not restore NVGPRS, and have interrupt handlers restore them explicitly in the cases that requires it. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-30-npiggin@gmail.com
2020-04-01powerpc/64s: Implement interrupt exit logic in CNicholas Piggin
Implement the bulk of interrupt return logic in C. The asm return code must handle a few cases: restoring full GPRs, and emulating stack store. The stack store emulation is significantly simplfied, rather than creating a new return frame and switching to that before performing the store, it uses the PACA to keep a scratch register around to perform the store. The asm return code is moved into 64e for now. The new logic has made allowance for 64e, but I don't have a full environment that works well to test it, and even booting in emulated qemu is not great for stress testing. 64e shouldn't be too far off working with this, given a bit more testing and auditing of the logic. This is slightly faster on a POWER9 (page fault speed increases about 1.1%), probably due to reduced mtmsrd. mpe: Includes fixes from Nick for _TIF_EMULATE_STACK_STORE handling (including the fast_interrupt_return path), to remove trace_hardirqs_on(), and fixes the interrupt-return part of the MSR_VSX restore bug caught by tm-unavailable selftest. mpe: Incorporate fix from Nick: The return-to-kernel path has to replay any soft-pending interrupts if it is returning to a context that had interrupts soft-enabled. It has to do this carefully and avoid plain enabling interrupts if this is an irq context, which can cause multiple nesting of interrupts on the stack, and other unexpected issues. The code which avoided this case got the soft-mask state wrong, and marked interrupts as enabled before going around again to retry. This seems to be mostly harmless except when PREEMPT=y, this calls preempt_schedule_irq with irqs apparently enabled and runs into a BUG in kernel/sched/core.c Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-29-npiggin@gmail.com
2020-04-01powerpc/64: Implement soft interrupt replay in CNicholas Piggin
When local_irq_enable() finds a pending soft-masked interrupt, it "replays" it by setting up registers like the initial interrupt entry, then calls into the low level handler to set up an interrupt stack frame and process the interrupt. This is not necessary, and uses more stack than needed. The high level interrupt handler can be called directly from C, with just pt_regs set up on stack. This should be faster and use less stack. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-28-npiggin@gmail.com
2020-04-01powerpc/64/syscall: Zero volatile registers when returningNicholas Piggin
Kernel addresses and potentially other sensitive data could be leaked in volatile registers after a syscall. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-27-npiggin@gmail.com
2020-04-01powerpc/64/sycall: Implement syscall entry/exit logic in CNicholas Piggin
System call entry and particularly exit code is beyond the limit of what is reasonable to implement in asm. This conversion moves all conditional branches out of the asm code, except for the case that all GPRs should be restored at exit. Null syscall test is about 5% faster after this patch, because the exit work is handled under local_irq_disable, and the hard mask and pending interrupt replay is handled after that, which avoids games with MSR. mpe: Includes subsequent fixes from Nick: This fixes 4 issues caught by TM selftests. First was a tm-syscall bug that hit due to tabort_syscall being called after interrupts were reconciled (in a subsequent patch), which led to interrupts being enabled before tabort_syscall was called. Rather than going through an un-reconciling interrupts for the return, I just go back to putting the test early in asm, the C-ification of that wasn't a big win anyway. Second is the syscall return _TIF_USER_WORK_MASK check would go into an infinite loop if _TIF_RESTORE_TM became set. The asm code uses _TIF_USER_WORK_MASK to brach to slowpath which includes restore_tm_state. Third is system call return was not calling restore_tm_state, I missed this completely (alhtough it's in the return from interrupt C conversion because when the asm syscall code encountered problems it would branch to the interrupt return code. Fourth is MSR_VEC missing from restore_math, which was caught by tm-unavailable selftest taking an unexpected facility unavailable interrupt when testing VSX unavailble exception with MSR.FP=1 MSR.VEC=1. Fourth case also has a fixup in a subsequent patch. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michal Suchanek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-26-npiggin@gmail.com
2020-04-01powerpc/64/sstep: Ifdef the deprecated fast endian switch syscallNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-25-npiggin@gmail.com
2020-04-01powerpc/64/syscall: Remove non-volatile GPR save optimisationNicholas Piggin
powerpc has an optimisation where interrupts avoid saving the non-volatile (or callee saved) registers to the interrupt stack frame if they are not required. Two problems with this are that an interrupt does not always know whether it will need non-volatiles; and if it does need them, they can only be saved from the entry-scoped asm code (because we don't control what the C compiler does with these registers). system calls are the most difficult: some system calls always require all registers (e.g., fork, to copy regs into the child). Sometimes registers are only required under certain conditions (e.g., tracing, signal delivery). These cases require ugly logic in the call chains (e.g., ppc_fork), and require a lot of logic to be implemented in asm. So remove the optimisation for system calls, and always save NVGPRs on entry. Modern high performance CPUs are not so sensitive, because the stores are dense in cache and can be hidden by other expensive work in the syscall path -- the null syscall selftests benchmark on POWER9 is not slowed (124.40ns before and 123.64ns after, i.e., within the noise). Other interrupts retain the NVGPR optimisation for now. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-24-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Soft NMI interrupt should not use ret_from_exceptNicholas Piggin
The soft NMI handler does not reconcile interrupt state, so it should not return via the normal ret_from_except path. Return like other NMIs, using the EXCEPTION_RESTORE_REGS macro. This becomes important when the scv interrupt is implemented, which must handle soft-masked interrupts that have r13 set to something other than the PACA -- returning to kernel in this case must restore r13. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-23-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Reconcile interrupts in system_resetNicholas Piggin
This adds IRQ_HARD_DIS to irq_happened. Although it doesn't seem to matter much because we're not allowed to enable irqs in an NMI handler, the soft-irq debugging code is becoming more strict about ensuring IRQ_HARD_DIS is in sync with MSR[EE], this may help avoid asserts or other issues. Add a comment explaining why MCE does not have this. Early machine check is generally much smaller and more contained code which will explode if you look at it wrong anyway as it runs in real mode, though there's an argument that we should do similar reconciling for the MCE as well. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-22-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Only test KVM in SRR interrupts when PR KVM is supportedNicholas Piggin
Apart from SRESET, MCE, and syscall (hcall variant), the SRR type interrupts are not escalated to hypervisor mode, so are delivered to the OS. When running PR KVM, the OS is the hypervisor, and the guest runs with MSR[PR]=1 (ie. usermode), so these interrupts must test if a guest was running when interrupted. These tests are required at the real-mode entry points because the PR KVM host runs with LPCR[AIL]=0. In HV KVM and nested HV KVM, the guest always receives these interrupts, so there is no need for the host to make this test. So remove the tests if PR KVM is not configured. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-21-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Add more comments for interrupt handlersNicholas Piggin
A few of the non-standard handlers are left uncommented. Some more description could be added to some. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-20-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Clean up SRR specifiersNicholas Piggin
Remove more magic numbers and replace with nicely named bools. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-19-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Re-inline some handlersNicholas Piggin
The reduction in interrupt entry size allows some handlers to be re-inlined. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-18-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Avoid touching the stack in hdecrementerNicholas Piggin
The hdec interrupt handler is reported to sometimes fire in Linux if KVM leaves it pending after a guest exists. This is harmless, so there is a no-op handler for it. The interrupt handler currently uses the regular kernel stack. Change this to avoid touching the stack entirely. This should be the last place where the regular Linux stack can be accessed with asynchronous interrupts (including PMI) soft-masked. It might be possible to take advantage of this invariant, e.g., to context switch the kernel stack SLB entry without clearing MSR[EE]. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-17-npiggin@gmail.com
2020-04-01powerpc/64s/exception: Trim unused arguments from KVMTEST macroNicholas Piggin
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200225173541.1549955-16-npiggin@gmail.com
generated by cgit (git 2.34.1) at 2025-09-13 23:26:21 +0000