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2023-02-13Merge branch kvm-arm64/virtual-cache-geometry into kvmarm/nextOliver Upton
* kvm-arm64/virtual-cache-geometry: : Virtualized cache geometry for KVM guests, courtesy of Akihiko Odaki. : : KVM/arm64 has always exposed the host cache geometry directly to the : guest, even though non-secure software should never perform CMOs by : Set/Way. This was slightly wrong, as the cache geometry was derived from : the PE on which the vCPU thread was running and not a sanitized value. : : All together this leads to issues migrating VMs on heterogeneous : systems, as the cache geometry saved/restored could be inconsistent. : : KVM/arm64 now presents 1 level of cache with 1 set and 1 way. The cache : geometry is entirely controlled by userspace, such that migrations from : older kernels continue to work. KVM: arm64: Mark some VM-scoped allocations as __GFP_ACCOUNT KVM: arm64: Normalize cache configuration KVM: arm64: Mask FEAT_CCIDX KVM: arm64: Always set HCR_TID2 arm64/cache: Move CLIDR macro definitions arm64/sysreg: Add CCSIDR2_EL1 arm64/sysreg: Convert CCSIDR_EL1 to automatic generation arm64: Allow the definition of UNKNOWN system register fields Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-13Merge branch arm64/for-next/sme2 into kvmarm/nextOliver Upton
Merge the SME2 branch to fix up a rather annoying conflict due to the EL2 finalization refactor. Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-11arm64: Add ARM64_HAS_NESTED_VIRT cpufeatureJintack Lim
Add a new ARM64_HAS_NESTED_VIRT feature to indicate that the CPU has the ARMv8.3 nested virtualization capability, together with the 'kvm-arm.mode=nested' command line option. This will be used to support nested virtualization in KVM. Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Jintack Lim <jintack.lim@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> [maz: moved the command-line option to kvm-arm.mode] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230209175820.1939006-2-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-10Merge branch 'for-next/signal' into for-next/coreCatalin Marinas
* for-next/signal: : Signal handling cleanups arm64/signal: Only read new data when parsing the ZT context arm64/signal: Only read new data when parsing the ZA context arm64/signal: Only read new data when parsing the SVE context arm64/signal: Avoid rereading context frame sizes arm64/signal: Make interface for restore_fpsimd_context() consistent arm64/signal: Remove redundant size validation from parse_user_sigframe() arm64/signal: Don't redundantly verify FPSIMD magic
2023-02-10Merge branch 'for-next/sysreg-hwcaps' into for-next/coreCatalin Marinas
* for-next/sysreg-hwcaps: : Make use of sysreg helpers for hwcaps arm64/cpufeature: Use helper macros to specify hwcaps arm64/cpufeature: Always use symbolic name for feature value in hwcaps arm64/sysreg: Initial unsigned annotations for ID registers arm64/sysreg: Initial annotation of signed ID registers arm64/sysreg: Allow enumerations to be declared as signed or unsigned
2023-02-10Merge branches 'for-next/sysreg', 'for-next/sme', 'for-next/kselftest', ↵Catalin Marinas
'for-next/misc', 'for-next/sme2', 'for-next/tpidr2', 'for-next/scs', 'for-next/compat-hwcap', 'for-next/ftrace', 'for-next/efi-boot-mmu-on', 'for-next/ptrauth' and 'for-next/pseudo-nmi', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: perf: arm_spe: Print the version of SPE detected perf: arm_spe: Add support for SPEv1.2 inverted event filtering perf: Add perf_event_attr::config3 drivers/perf: fsl_imx8_ddr_perf: Remove set-but-not-used variable perf: arm_spe: Support new SPEv1.2/v8.7 'not taken' event perf: arm_spe: Use new PMSIDR_EL1 register enums perf: arm_spe: Drop BIT() and use FIELD_GET/PREP accessors arm64/sysreg: Convert SPE registers to automatic generation arm64: Drop SYS_ from SPE register defines perf: arm_spe: Use feature numbering for PMSEVFR_EL1 defines perf/marvell: Add ACPI support to TAD uncore driver perf/marvell: Add ACPI support to DDR uncore driver perf/arm-cmn: Reset DTM_PMU_CONFIG at probe drivers/perf: hisi: Extract initialization of "cpa_pmu->pmu" drivers/perf: hisi: Simplify the parameters of hisi_pmu_init() drivers/perf: hisi: Advertise the PERF_PMU_CAP_NO_EXCLUDE capability * for-next/sysreg: : arm64 sysreg and cpufeature fixes/updates KVM: arm64: Use symbolic definition for ISR_EL1.A arm64/sysreg: Add definition of ISR_EL1 arm64/sysreg: Add definition for ICC_NMIAR1_EL1 arm64/cpufeature: Remove 4 bit assumption in ARM64_FEATURE_MASK() arm64/sysreg: Fix errors in 32 bit enumeration values arm64/cpufeature: Fix field sign for DIT hwcap detection * for-next/sme: : SME-related updates arm64/sme: Optimise SME exit on syscall entry arm64/sme: Don't use streaming mode to probe the maximum SME VL arm64/ptrace: Use system_supports_tpidr2() to check for TPIDR2 support * for-next/kselftest: (23 commits) : arm64 kselftest fixes and improvements kselftest/arm64: Don't require FA64 for streaming SVE+ZA tests kselftest/arm64: Copy whole EXTRA context kselftest/arm64: Fix enumeration of systems without 128 bit SME for SSVE+ZA kselftest/arm64: Fix enumeration of systems without 128 bit SME kselftest/arm64: Don't require FA64 for streaming SVE tests kselftest/arm64: Limit the maximum VL we try to set via ptrace kselftest/arm64: Correct buffer size for SME ZA storage kselftest/arm64: Remove the local NUM_VL definition kselftest/arm64: Verify simultaneous SSVE and ZA context generation kselftest/arm64: Verify that SSVE signal context has SVE_SIG_FLAG_SM set kselftest/arm64: Remove spurious comment from MTE test Makefile kselftest/arm64: Support build of MTE tests with clang kselftest/arm64: Initialise current at build time in signal tests kselftest/arm64: Don't pass headers to the compiler as source kselftest/arm64: Remove redundant _start labels from FP tests kselftest/arm64: Fix .pushsection for strings in FP tests kselftest/arm64: Run BTI selftests on systems without BTI kselftest/arm64: Fix test numbering when skipping tests kselftest/arm64: Skip non-power of 2 SVE vector lengths in fp-stress kselftest/arm64: Only enumerate power of two VLs in syscall-abi ... * for-next/misc: : Miscellaneous arm64 updates arm64/mm: Intercept pfn changes in set_pte_at() Documentation: arm64: correct spelling arm64: traps: attempt to dump all instructions arm64: Apply dynamic shadow call stack patching in two passes arm64: el2_setup.h: fix spelling typo in comments arm64: Kconfig: fix spelling arm64: cpufeature: Use kstrtobool() instead of strtobool() arm64: Avoid repeated AA64MMFR1_EL1 register read on pagefault path arm64: make ARCH_FORCE_MAX_ORDER selectable * for-next/sme2: (23 commits) : Support for arm64 SME 2 and 2.1 arm64/sme: Fix __finalise_el2 SMEver check kselftest/arm64: Remove redundant _start labels from zt-test kselftest/arm64: Add coverage of SME 2 and 2.1 hwcaps kselftest/arm64: Add coverage of the ZT ptrace regset kselftest/arm64: Add SME2 coverage to syscall-abi kselftest/arm64: Add test coverage for ZT register signal frames kselftest/arm64: Teach the generic signal context validation about ZT kselftest/arm64: Enumerate SME2 in the signal test utility code kselftest/arm64: Cover ZT in the FP stress test kselftest/arm64: Add a stress test program for ZT0 arm64/sme: Add hwcaps for SME 2 and 2.1 features arm64/sme: Implement ZT0 ptrace support arm64/sme: Implement signal handling for ZT arm64/sme: Implement context switching for ZT0 arm64/sme: Provide storage for ZT0 arm64/sme: Add basic enumeration for SME2 arm64/sme: Enable host kernel to access ZT0 arm64/sme: Manually encode ZT0 load and store instructions arm64/esr: Document ISS for ZT0 being disabled arm64/sme: Document SME 2 and SME 2.1 ABI ... * for-next/tpidr2: : Include TPIDR2 in the signal context kselftest/arm64: Add test case for TPIDR2 signal frame records kselftest/arm64: Add TPIDR2 to the set of known signal context records arm64/signal: Include TPIDR2 in the signal context arm64/sme: Document ABI for TPIDR2 signal information * for-next/scs: : arm64: harden shadow call stack pointer handling arm64: Stash shadow stack pointer in the task struct on interrupt arm64: Always load shadow stack pointer directly from the task struct * for-next/compat-hwcap: : arm64: Expose compat ARMv8 AArch32 features (HWCAPs) arm64: Add compat hwcap SSBS arm64: Add compat hwcap SB arm64: Add compat hwcap I8MM arm64: Add compat hwcap ASIMDBF16 arm64: Add compat hwcap ASIMDFHM arm64: Add compat hwcap ASIMDDP arm64: Add compat hwcap FPHP and ASIMDHP * for-next/ftrace: : Add arm64 support for DYNAMICE_FTRACE_WITH_CALL_OPS arm64: avoid executing padding bytes during kexec / hibernation arm64: Implement HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS arm64: ftrace: Update stale comment arm64: patching: Add aarch64_insn_write_literal_u64() arm64: insn: Add helpers for BTI arm64: Extend support for CONFIG_FUNCTION_ALIGNMENT ACPI: Don't build ACPICA with '-Os' Compiler attributes: GCC cold function alignment workarounds ftrace: Add DYNAMIC_FTRACE_WITH_CALL_OPS * for-next/efi-boot-mmu-on: : Permit arm64 EFI boot with MMU and caches on arm64: kprobes: Drop ID map text from kprobes blacklist arm64: head: Switch endianness before populating the ID map efi: arm64: enter with MMU and caches enabled arm64: head: Clean the ID map and the HYP text to the PoC if needed arm64: head: avoid cache invalidation when entering with the MMU on arm64: head: record the MMU state at primary entry arm64: kernel: move identity map out of .text mapping arm64: head: Move all finalise_el2 calls to after __enable_mmu * for-next/ptrauth: : arm64 pointer authentication cleanup arm64: pauth: don't sign leaf functions arm64: unify asm-arch manipulation * for-next/pseudo-nmi: : Pseudo-NMI code generation optimisations arm64: irqflags: use alternative branches for pseudo-NMI logic arm64: add ARM64_HAS_GIC_PRIO_RELAXED_SYNC cpucap arm64: make ARM64_HAS_GIC_PRIO_MASKING depend on ARM64_HAS_GIC_CPUIF_SYSREGS arm64: rename ARM64_HAS_IRQ_PRIO_MASKING to ARM64_HAS_GIC_PRIO_MASKING arm64: rename ARM64_HAS_SYSREG_GIC_CPUIF to ARM64_HAS_GIC_CPUIF_SYSREGS
2023-02-09efi: arm64: Wire up BTI annotation in memory attributes tableArd Biesheuvel
UEFI v2.10 extends the EFI memory attributes table with a flag that indicates whether or not all RuntimeServicesCode regions were constructed with BTI landing pads, permitting the OS to map these regions with BTI restrictions enabled. So let's take this into account on arm64. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will@kernel.org>
2023-02-08arm64: Support Clang UBSAN trap codes for better reportingKees Cook
When building with CONFIG_UBSAN_TRAP=y on arm64, Clang encodes the UBSAN check (handler) type in the esr. Extract this and actually report these traps as coming from the specific UBSAN check that tripped. Before: Internal error: BRK handler: 00000000f20003e8 [#1] PREEMPT SMP After: Internal error: UBSAN: shift out of bounds: 00000000f2005514 [#1] PREEMPT SMP Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Mukesh Ojha <quic_mojha@quicinc.com> Reviewed-by: Fangrui Song <maskray@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: John Stultz <jstultz@google.com> Cc: Yongqin Liu <yongqin.liu@linaro.org> Cc: Sami Tolvanen <samitolvanen@google.com> Cc: Yury Norov <yury.norov@gmail.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Marco Elver <elver@google.com> Cc: linux-arm-kernel@lists.infradead.org Cc: llvm@lists.linux.dev Signed-off-by: Kees Cook <keescook@chromium.org>
2023-02-07arm64: kprobes: Drop ID map text from kprobes blacklistArd Biesheuvel
The ID mapped text region is never accessed via the normal kernel mapping of text, and so it was moved into .rodata instead. This means it is no longer considered as a suitable place for kprobes by default, and the explicit blacklist is unnecessary, and actually results in an error message at boot: kprobes: Failed to populate blacklist (error -22), kprobes not restricted, be careful using them! So stop blacklisting the ID map text explicitly. Fixes: af7249b317e4 ("arm64: kernel: move identity map out of .text mapping") Reported-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20230204101807.2862321-1-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-06arm64/sme: Fix __finalise_el2 SMEver checkMarc Zyngier
When checking for ID_AA64SMFR0_EL1.SMEver, __check_override assumes that the ID_AA64SMFR0_EL1 value is in x1, and the intent of the code is to reuse value read a few lines above. However, as the comment says at the beginning of the macro, x1 will be clobbered, and the checks always fails. The easiest fix is just to reload the id register before checking it. Fixes: f122576f3533 ("arm64/sme: Enable host kernel to access ZT0") Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-04efi: Discover BTI support in runtime services regionsArd Biesheuvel
Add the generic plumbing to detect whether or not the runtime code regions were constructed with BTI/IBT landing pads by the firmware, permitting the OS to enable enforcement when mapping these regions into the OS's address space. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org>
2023-02-02KVM: arm64: Introduce finalise_el2_state macroQuentin Perret
Factor out the first half of the finalise_el2 function into a macro to allow its reuse from the nVHE PSCI relay code. While at it, make the register allocation parametric for the check_override macros as they are now more widely exposed. No functional changes intended. Signed-off-by: Quentin Perret <qperret@google.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20230201103755.1398086-3-qperret@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-01arm64/signal: Only read new data when parsing the ZT contextMark Brown
When we parse the ZT signal context we read the entire context from userspace, including the generic signal context header which was already read by parse_user_sigframe() and padding bytes that we ignore. Avoid the possibility of relying on the second read of the data read twice by only reading the data which we are actually going to use. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-7-4545c94b20ff@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01arm64/signal: Only read new data when parsing the ZA contextMark Brown
When we parse the ZA signal context we read the entire context from userspace, including the generic signal context header which was already read by parse_user_sigframe() and padding bytes that we ignore. Avoid the possibility of relying on the second read of the data read twice by only reading the data which we are actually going to use. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-6-4545c94b20ff@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01arm64/signal: Only read new data when parsing the SVE contextMark Brown
When we parse the SVE signal context we read the entire context from userspace, including the generic signal context header which was already read by parse_user_sigframe() and padding bytes that we ignore. Avoid the possibility of relying on the second read of the data read twice by only reading the data which we are actually going to use. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-5-4545c94b20ff@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01arm64/signal: Avoid rereading context frame sizesMark Brown
We need to read the sizes of the signal context frames as part of parsing the overall signal context in parse_user_sigframe(). In the cases where we defer frame specific parsing to other functions those functions (other than the recently added TPIDR2 parser) reread the size and validate the version they read, opening the possibility that the value may change. Avoid this possibility by passing the size read in parse_user_sigframe() through user_ctxs and referring to that. For consistency we move the size check for the TPIDR2 context into the TPIDR2 parsing function. Note that for SVE, ZA and ZT contexts we still read the size again but after this change we no longer use the value, further changes will avoid the read. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-4-4545c94b20ff@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01arm64/signal: Make interface for restore_fpsimd_context() consistentMark Brown
Instead of taking a pointer to struct user_ctxs like the other two restore_blah_context() functions the FPSIMD function takes a pointer to the user struct it should read. Change it to be consistent with the rest, both for consistency and to prepare for changes which avoid rereading data that has already been read by the core parsing code. There should be no functional change from this patch. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-3-4545c94b20ff@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01arm64/signal: Remove redundant size validation from parse_user_sigframe()Mark Brown
There is some minimal size validation in parse_user_sigframe() however all of the individual parsing functions perform frame specific validation of the sizing information, remove the frame specific size checks in the core so that there isn't any confusion about what we validate for size. Since the checks in the SVE and ZA parsing are after we have read the relevant context and since they won't report an error if the frame is undersized they are adjusted to check for this before doing anything else. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-2-4545c94b20ff@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01arm64/signal: Don't redundantly verify FPSIMD magicMark Brown
We validate that the magic in the struct fpsimd_context is correct in restore_fpsimd_context() but this is redundant since parse_user_sigframe() uses this magic to decide to call the function in the first place. Remove the extra validation. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221212-arm64-signal-cleanup-v3-1-4545c94b20ff@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01Merge branches 'for-next/tpidr2' and 'for-next/sme2' into for-next/signalCatalin Marinas
Patches on this branch depend on the branches merged above.
2023-02-01arm64/cpufeature: Use helper macros to specify hwcapsMark Brown
At present the hwcaps are hard to read and a bit error prone since the macros used to specify matches require us to write out the register name multiple times and explicitly specify the width of the field, hopefully using the correct constant. Now that all the ID registers are generated we can improve this somewhat by redoing the macros so that we specify the register, field and minimum value symbolically and use token pasting to initialise the capability struct with the appropriate values. We move from specifying like this: HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_EL1_BT_SHIFT, 4, FTR_UNSIGNED, ID_AA64PFR1_EL1_BT_IMP, CAP_HWCAP, KERNEL_HWCAP_BTI), to this: HWCAP_CAP(ID_AA64PFR1_EL1, BT, IMP, CAP_HWCAP, KERNEL_HWCAP_BTI), which is shorter due to having less duplicate information and makes it much harder to make an error like specifying the wrong field width or an invalid enumeration value since everything must be a constant defined for the sysreg and names are only typed once. There should be no functional effect from this change, a check of the generated .rodata showed no differences. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221207-arm64-sysreg-helpers-v4-5-25b6b3fb9d18@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01arm64/cpufeature: Always use symbolic name for feature value in hwcapsMark Brown
Our table of hwcaps sometimes uses the defined constant to specify the enumeration value they are attempting to match but in some cases an unadorned number is used. In preparation for using helper macros to to specify the hwcaps less verbosely replace the magic numbers with their constants, this will hopefully make the conversion to helper macros easier to review. There should be no functional effect from this change, a check of the generate .rodata showed no differences. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20221207-arm64-sysreg-helpers-v4-4-25b6b3fb9d18@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-02-01Merge branches 'for-next/sysreg', 'for-next/compat-hwcap' and ↵Catalin Marinas
'for-next/sme2' into for-next/sysreg-hwcaps Patches on this branch depend on the branches merged above.
2023-01-31arm64: add ARM64_HAS_GIC_PRIO_RELAXED_SYNC cpucapMark Rutland
When Priority Mask Hint Enable (PMHE) == 0b1, the GIC may use the PMR value to determine whether to signal an IRQ to a PE, and consequently after a change to the PMR value, a DSB SY may be required to ensure that interrupts are signalled to a CPU in finite time. When PMHE == 0b0, interrupts are always signalled to the relevant PE, and all masking occurs locally, without requiring a DSB SY. Since commit: f226650494c6aa87 ("arm64: Relax ICC_PMR_EL1 accesses when ICC_CTLR_EL1.PMHE is clear") ... we handle this dynamically: in most cases a static key is used to determine whether to issue a DSB SY, but the entry code must read from ICC_CTLR_EL1 as static keys aren't accessible from plain assembly. It would be much nicer to use an alternative instruction sequence for the DSB, as this would avoid the need to read from ICC_CTLR_EL1 in the entry code, and for most other code this will result in simpler code generation with fewer instructions and fewer branches. This patch adds a new ARM64_HAS_GIC_PRIO_RELAXED_SYNC cpucap which is only set when ICC_CTLR_EL1.PMHE == 0b0 (and GIC priority masking is in use). This allows us to replace the existing users of the `gic_pmr_sync` static key with alternative sequences which default to a DSB SY and are relaxed to a NOP when PMHE is not in use. The entry assembly management of the PMR is slightly restructured to use a branch (rather than multiple NOPs) when priority masking is not in use. This is more in keeping with other alternatives in the entry assembly, and permits the use of a separate alternatives for the PMHE-dependent DSB SY (and removal of the conditional branch this currently requires). For consistency I've adjusted both the save and restore paths. According to bloat-o-meter, when building defconfig + CONFIG_ARM64_PSEUDO_NMI=y this shrinks the kernel text by ~4KiB: | add/remove: 4/2 grow/shrink: 42/310 up/down: 332/-5032 (-4700) The resulting vmlinux is ~66KiB smaller, though the resulting Image size is unchanged due to padding and alignment: | [mark@lakrids:~/src/linux]% ls -al vmlinux-* | -rwxr-xr-x 1 mark mark 137508344 Jan 17 14:11 vmlinux-after | -rwxr-xr-x 1 mark mark 137575440 Jan 17 13:49 vmlinux-before | [mark@lakrids:~/src/linux]% ls -al Image-* | -rw-r--r-- 1 mark mark 38777344 Jan 17 14:11 Image-after | -rw-r--r-- 1 mark mark 38777344 Jan 17 13:49 Image-before Prior to this patch we did not verify the state of ICC_CTLR_EL1.PMHE on secondary CPUs. As of this patch this is verified by the cpufeature code when using GIC priority masking (i.e. when using pseudo-NMIs). Note that since commit: 7e3a57fa6ca831fa ("arm64: Document ICC_CTLR_EL3.PMHE setting requirements") ... Documentation/arm64/booting.rst specifies: | - ICC_CTLR_EL3.PMHE (bit 6) must be set to the same value across | all CPUs the kernel is executing on, and must stay constant | for the lifetime of the kernel. ... so that should not adversely affect any compliant systems, and as we'll only check for the absense of PMHE when using pseudo-NMIs, this will only fire when such mismatch will adversely affect the system. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230130145429.903791-5-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-31arm64: make ARM64_HAS_GIC_PRIO_MASKING depend on ARM64_HAS_GIC_CPUIF_SYSREGSMark Rutland
Currently the arm64_cpu_capabilities structure for ARM64_HAS_GIC_PRIO_MASKING open-codes the same CPU field definitions as the arm64_cpu_capabilities structure for ARM64_HAS_GIC_CPUIF_SYSREGS, so that can_use_gic_priorities() can use has_useable_gicv3_cpuif(). This duplication isn't ideal for the legibility of the code, and sets a bad example for any ARM64_HAS_GIC_* definitions added by subsequent patches. Instead, have ARM64_HAS_GIC_PRIO_MASKING check for the ARM64_HAS_GIC_CPUIF_SYSREGS cpucap, and add a comment explaining why this is safe. Subsequent patches will use the same pattern where one cpucap depends upon another. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230130145429.903791-4-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-31arm64: rename ARM64_HAS_IRQ_PRIO_MASKING to ARM64_HAS_GIC_PRIO_MASKINGMark Rutland
Subsequent patches will add more GIC-related cpucaps. When we do so, it would be nice to give them a consistent HAS_GIC_* prefix. In preparation for doing so, this patch renames the existing ARM64_HAS_IRQ_PRIO_MASKING cap to ARM64_HAS_GIC_PRIO_MASKING. The cpucaps file was hand-modified; all other changes were scripted with: find . -type f -name '*.[chS]' -print0 | \ xargs -0 sed -i 's/ARM64_HAS_IRQ_PRIO_MASKING/ARM64_HAS_GIC_PRIO_MASKING/' There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230130145429.903791-3-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-31arm64: rename ARM64_HAS_SYSREG_GIC_CPUIF to ARM64_HAS_GIC_CPUIF_SYSREGSMark Rutland
Subsequent patches will add more GIC-related cpucaps. When we do so, it would be nice to give them a consistent HAS_GIC_* prefix. In preparation for doing so, this patch renames the existing ARM64_HAS_SYSREG_GIC_CPUIF cap to ARM64_HAS_GIC_CPUIF_SYSREGS. The 'CPUIF_SYSREGS' suffix is chosen so that this will be ordered ahead of other ARM64_HAS_GIC_* definitions in subsequent patches. The cpucaps file was hand-modified; all other changes were scripted with: find . -type f -name '*.[chS]' -print0 | \ xargs -0 sed -i 's/ARM64_HAS_SYSREG_GIC_CPUIF/ARM64_HAS_GIC_CPUIF_SYSREGS/' There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230130145429.903791-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-31cacheinfo: Remove unused check in init_cache_level()Pierre Gondois
commit e75d18cecbb3 ("arm64: cacheinfo: Fix incorrect assignment of signed error value to unsigned fw_level") checks the fw_level value in init_cache_level() in case the value is negative. Remove this check as the error code is not returned through fw_level anymore, and reset fw_level if acpi_get_cache_info() failed. This allows to try fetching the cache information from clidr_el1. Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Link: https://lore.kernel.org/r/20230124154053.355376-4-pierre.gondois@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31cacheinfo: Make default acpi_get_cache_info() return an errorPierre Gondois
commit bd500361a937 ("ACPI: PPTT: Update acpi_find_last_cache_level() to acpi_get_cache_info()") updates the prototype of acpi_get_cache_info(). The cache 'levels' is update through a pointer and not the return value of the function. If CONFIG_ACPI_PPTT is not defined, acpi_get_cache_info() doesn't update its *levels and *split_levels parameters and returns 0. This can lead to a faulty behaviour. Make acpi_get_cache_info() return an error code if CONFIG_ACPI_PPTT is not defined. Also, In init_cache_level(), if no PPTT is present or CONFIG_ACPI_PPTT is not defined, instead of aborting if acpi_get_cache_info() returns an error code, just continue. This allows to try fetching the cache information from clidr_el1. Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Link: https://lore.kernel.org/r/20230124154053.355376-3-pierre.gondois@arm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-31Merge tag 'v6.2-rc6' into sched/core, to pick up fixesIngo Molnar
Pick up fixes before merging another batch of cpuidle updates. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2023-01-27arm64: traps: attempt to dump all instructionsMark Rutland
Currently dump_kernel_instr() dumps a few instructions around the pt_regs::pc value, dumping 4 instructions before the PC before dumping the instruction at the PC. If an attempt to read an instruction fails, it gives up and does not attempt to dump any subsequent instructions. This is unfortunate when the pt_regs::pc value points to the start of a page with a leading guard page, where the instruction at the PC can be read, but prior instructions cannot. This patch makes dump_kernel_instr() attempt to dump each instruction regardless of whether reading a prior instruction could be read, which gives a more useful code dump in such cases. When an instruction cannot be read, it is reported as "????????", which cannot be confused with a hex value, For example, with a `UDF #0` (AKA 0x00000000) early in the kexec control page, we'll now get the following code dump: | Internal error: Oops - Undefined instruction: 0000000002000000 [#1] SMP | Modules linked in: | CPU: 0 PID: 261 Comm: kexec Not tainted 6.2.0-rc5+ #26 | Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 | pstate: 604003c5 (nZCv DAIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : 0x48c00000 | lr : machine_kexec+0x190/0x200 | sp : ffff80000d36ba80 | x29: ffff80000d36ba80 x28: ffff000002dfc380 x27: 0000000000000000 | x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | x23: ffff80000a9f7858 x22: 000000004c460000 x21: 0000000000000010 | x20: 00000000ad821000 x19: ffff000000aa0000 x18: 0000000000000006 | x17: ffff8000758a2000 x16: ffff800008000000 x15: ffff80000d36b568 | x14: 0000000000000000 x13: ffff80000d36b707 x12: ffff80000a9bf6e0 | x11: 00000000ffffdfff x10: ffff80000aaaf8e0 x9 : ffff80000815eff8 | x8 : 000000000002ffe8 x7 : c0000000ffffdfff x6 : 00000000000affa8 | x5 : 0000000000001fff x4 : 0000000000000001 x3 : ffff80000a263008 | x2 : ffff80000a9e20f8 x1 : 0000000048c00000 x0 : ffff000000aa0000 | Call trace: | 0x48c00000 | kernel_kexec+0x88/0x138 | __do_sys_reboot+0x108/0x288 | __arm64_sys_reboot+0x2c/0x40 | invoke_syscall+0x78/0x140 | el0_svc_common.constprop.0+0x4c/0x100 | do_el0_svc+0x34/0x80 | el0_svc+0x34/0x140 | el0t_64_sync_handler+0xf4/0x140 | el0t_64_sync+0x194/0x1c0 | Code: ???????? ???????? ???????? ???????? (00000000) | ---[ end trace 0000000000000000 ]--- | Kernel panic - not syncing: Oops - Undefined instruction: Fatal exception | Kernel Offset: disabled | CPU features: 0x002000,00050108,c8004203 | Memory Limit: none Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230127121256.2141368-1-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-27arm64: avoid executing padding bytes during kexec / hibernationMark Rutland
Currently we rely on the HIBERNATE_TEXT section starting with the entry point to swsusp_arch_suspend_exit, and the KEXEC_TEXT section starting with the entry point to arm64_relocate_new_kernel. In both cases we copy the entire section into a dynamically-allocated page, and then later branch to the start of this page. SYM_FUNC_START() will align the function entry points to CONFIG_FUNCTION_ALIGNMENT, and when the linker later processes the assembled code it will place padding bytes before the function entry point if the location counter was not already sufficiently aligned. The linker happens to use the value zero for these padding bytes. This padding may end up being applied whenever CONFIG_FUNCTION_ALIGNMENT is greater than 4, which can be the case with CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B=y or CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS=y. When such padding is applied, attempting to kexec or resume from hibernate will result ina crash: the kernel will branch to the padding bytes as the start of the dynamically-allocated page, and as those bytes are zero they will decode as UDF #0, which reliably triggers an UNDEFINED exception. For example: | # ./kexec --reuse-cmdline -f Image | [ 46.965800] kexec_core: Starting new kernel | [ 47.143641] psci: CPU1 killed (polled 0 ms) | [ 47.233653] psci: CPU2 killed (polled 0 ms) | [ 47.323465] psci: CPU3 killed (polled 0 ms) | [ 47.324776] Bye! | [ 47.327072] Internal error: Oops - Undefined instruction: 0000000002000000 [#1] SMP | [ 47.328510] Modules linked in: | [ 47.329086] CPU: 0 PID: 259 Comm: kexec Not tainted 6.2.0-rc5+ #3 | [ 47.330223] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 | [ 47.331497] pstate: 604003c5 (nZCv DAIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) | [ 47.332782] pc : 0x43a95000 | [ 47.333338] lr : machine_kexec+0x190/0x1e0 | [ 47.334169] sp : ffff80000d293b70 | [ 47.334845] x29: ffff80000d293b70 x28: ffff000002cc0000 x27: 0000000000000000 | [ 47.336292] x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 | [ 47.337744] x23: ffff80000a837858 x22: 0000000048ec9000 x21: 0000000000000010 | [ 47.339192] x20: 00000000adc83000 x19: ffff000000827000 x18: 0000000000000006 | [ 47.340638] x17: ffff800075a61000 x16: ffff800008000000 x15: ffff80000d293658 | [ 47.342085] x14: 0000000000000000 x13: ffff80000d2937f7 x12: ffff80000a7ff6e0 | [ 47.343530] x11: 00000000ffffdfff x10: ffff80000a8ef8e0 x9 : ffff80000813ef00 | [ 47.344976] x8 : 000000000002ffe8 x7 : c0000000ffffdfff x6 : 00000000000affa8 | [ 47.346431] x5 : 0000000000001fff x4 : 0000000000000001 x3 : ffff80000a0a3008 | [ 47.347877] x2 : ffff80000a8220f8 x1 : 0000000043a95000 x0 : ffff000000827000 | [ 47.349334] Call trace: | [ 47.349834] 0x43a95000 | [ 47.350338] kernel_kexec+0x88/0x100 | [ 47.351070] __do_sys_reboot+0x108/0x268 | [ 47.351873] __arm64_sys_reboot+0x2c/0x40 | [ 47.352689] invoke_syscall+0x78/0x108 | [ 47.353458] el0_svc_common.constprop.0+0x4c/0x100 | [ 47.354426] do_el0_svc+0x34/0x50 | [ 47.355102] el0_svc+0x34/0x108 | [ 47.355747] el0t_64_sync_handler+0xf4/0x120 | [ 47.356617] el0t_64_sync+0x194/0x198 | [ 47.357374] Code: bad PC value | [ 47.357999] ---[ end trace 0000000000000000 ]--- | [ 47.358937] Kernel panic - not syncing: Oops - Undefined instruction: Fatal exception | [ 47.360515] Kernel Offset: disabled | [ 47.361230] CPU features: 0x002000,00050108,c8004203 | [ 47.362232] Memory Limit: none Note: Unfortunately the code dump reports "bad PC value" as it attempts to dump some instructions prior to the UDF (i.e. before the start of the page), and terminates early upon a fault, obscuring the problem. This patch fixes this issue by aligning the section starter markes to CONFIG_FUNCTION_ALIGNMENT using the ALIGN_FUNCTION() helper, which ensures that the linker never needs to place padding bytes within the section. Assertions are added to verify each section begins with the function we expect, making our implicit requirement explicit. In future it might be nice to rework the kexec and hibernation code to decouple the section start from the entry point, but that involves much more significant changes that come with a higher risk of error, so I've tried to keep this fix as simple as possible for now. Fixes: 47a15aa54427 ("arm64: Extend support for CONFIG_FUNCTION_ALIGNMENT") Reported-by: CKI Project <cki-project@redhat.com> Link: https://lore.kernel.org/linux-arm-kernel/29992.123012504212600261@us-mta-139.us.mimecast.lan/ Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-26arm64: Apply dynamic shadow call stack patching in two passesArd Biesheuvel
Code patching for the dynamically enabled shadow call stack comes down to finding PACIASP and AUTIASP instructions -which behave as NOPs on cores that do not implement pointer authentication- and converting them into shadow call stack pushes and pops, respectively. Due to past bad experiences with the highly complex and overengineered DWARF standard that describes the unwind metadata that we are using to locate these instructions, let's make this patching logic a little bit more robust so that any issues with the unwind metadata detected at boot time can de dealt with gracefully. The DWARF annotations that are used for this are emitted at function granularity, and due to the fact that the instructions we are patching will simply behave as NOPs if left unpatched, we can abort on errors as long as we don't leave any functions in a half-patched state. So do a dry run of each FDE frame (covering a single function) before performing the actual patching, and give up if the DWARF metadata cannot be understood. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Will Deacon <will@kernel.org> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Link: https://lore.kernel.org/r/20221213142849.1629026-1-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-26arm64: head: Switch endianness before populating the ID mapArd Biesheuvel
Ensure that the endianness used for populating the ID map matches the endianness that the running kernel will be using, as this is no longer guaranteed now that create_idmap() is invoked before init_kernel_el(). Note that doing so is only safe if the MMU is off, as switching the endianness with the MMU on results in the active ID map to become invalid. So also clear the M bit when toggling the EE bit in SCTLR, and mark the MMU as disabled at boot. Note that the same issue has resulted in preserve_boot_args() recording the contents of registers X0 ... X3 in the wrong byte order, although this is arguably a very minor concern. Fixes: 32b135a7fafe ("arm64: head: avoid cache invalidation when entering with the MMU on") Reported-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20230125185910.962733-1-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24efi: arm64: enter with MMU and caches enabledArd Biesheuvel
Instead of cleaning the entire loaded kernel image to the PoC and disabling the MMU and caches before branching to the kernel's bare metal entry point, we can leave the MMU and caches enabled, and rely on EFI's cacheable 1:1 mapping of all of system RAM (which is mandated by the spec) to populate the initial page tables. This removes the need for managing coherency in software, which is tedious and error prone. Note that we still need to clean the executable region of the image to the PoU if this is required for I/D coherency, but only if we actually decided to move the image in memory, as otherwise, this will have been taken care of by the loader. This change affects both the builtin EFI stub as well as the zboot decompressor, which now carries the entire EFI stub along with the decompression code and the compressed image. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230111102236.1430401-7-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24arm64: head: Clean the ID map and the HYP text to the PoC if neededArd Biesheuvel
If we enter with the MMU and caches enabled, the bootloader may not have performed any cache maintenance to the PoC. So clean the ID mapped page to the PoC, to ensure that instruction and data accesses with the MMU off see the correct data. For similar reasons, clean all the HYP text to the PoC as well when entering at EL2 with the MMU and caches enabled. Note that this means primary_entry() itself needs to be moved into the ID map as well, as we will return from init_kernel_el() with the MMU and caches off. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230111102236.1430401-6-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24arm64: head: avoid cache invalidation when entering with the MMU onArd Biesheuvel
If we enter with the MMU on, there is no need for explicit cache invalidation for stores to memory, as they will be coherent with the caches. Let's take advantage of this, and create the ID map with the MMU still enabled if that is how we entered, and avoid any cache invalidation calls in that case. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230111102236.1430401-5-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24arm64: head: record the MMU state at primary entryArd Biesheuvel
Prepare for being able to deal with primary entry with the MMU and caches enabled, by recording whether or not we entered with the MMU on in register x19 and in a global variable. (Note that setting this variable to '1' does not require cache invalidation, nor is it required for storing the bootargs in that case, so omit the cache maintenance). Since boot with the MMU and caches enabled is not permitted by the bare metal boot protocol, ensure that a diagnostic is emitted and a taint bit set if the MMU was found to be enabled on a non-EFI boot, and panic() once the console is likely to be up. We will make an exception for EFI boot later, which has strict requirements for the mapping of system memory, permitting us to relax the boot protocol and hand over from the EFI stub to the core kernel with MMU and caches left enabled. While at it, add 'pre_disable_mmu_workaround' macro invocations to init_kernel_el, as its manipulation of SCTLR_ELx may amount to disabling of the MMU after subsequent patches. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230111102236.1430401-4-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24arm64: kernel: move identity map out of .text mappingArd Biesheuvel
Reorganize the ID map slightly so that only code that is executed with the MMU off or via the 1:1 mapping remains. This allows us to move the identity map out of the .text segment, as it will no longer need executable permissions via the kernel mapping. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230111102236.1430401-3-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24arm64: head: Move all finalise_el2 calls to after __enable_mmuArd Biesheuvel
In the primary boot path, finalise_el2() is called much later than on the secondary boot or resume-from-suspend paths, and this does not appear to be intentional. Since we aim to do as little as possible before enabling the MMU and caches, align secondary and resume with primary boot, and defer the call to after the MMU is turned on. This also removes the need to clean finalise_el2() to the PoC once we enable support for booting with the MMU on. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230111102236.1430401-2-ardb@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24arm64: Implement HAVE_DYNAMIC_FTRACE_WITH_CALL_OPSMark Rutland
This patch enables support for DYNAMIC_FTRACE_WITH_CALL_OPS on arm64. This allows each ftrace callsite to provide an ftrace_ops to the common ftrace trampoline, allowing each callsite to invoke distinct tracer functions without the need to fall back to list processing or to allocate custom trampolines for each callsite. This significantly speeds up cases where multiple distinct trace functions are used and callsites are mostly traced by a single tracer. The main idea is to place a pointer to the ftrace_ops as a literal at a fixed offset from the function entry point, which can be recovered by the common ftrace trampoline. Using a 64-bit literal avoids branch range limitations, and permits the ops to be swapped atomically without special considerations that apply to code-patching. In future this will also allow for the implementation of DYNAMIC_FTRACE_WITH_DIRECT_CALLS without branch range limitations by using additional fields in struct ftrace_ops. As noted in the core patch adding support for DYNAMIC_FTRACE_WITH_CALL_OPS, this approach allows for directly invoking ftrace_ops::func even for ftrace_ops which are dynamically-allocated (or part of a module), without going via ftrace_ops_list_func. Currently, this approach is not compatible with CLANG_CFI, as the presence/absence of pre-function NOPs changes the offset of the pre-function type hash, and there's no existing mechanism to ensure a consistent offset for instrumented and uninstrumented functions. When CLANG_CFI is enabled, the existing scheme with a global ops->func pointer is used, and there should be no functional change. I am currently working with others to allow the two to work together in future (though this will liekly require updated compiler support). I've benchamrked this with the ftrace_ops sample module [1], which is not currently upstream, but available at: https://lore.kernel.org/lkml/20230103124912.2948963-1-mark.rutland@arm.com git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git ftrace-ops-sample-20230109 Using that module I measured the total time taken for 100,000 calls to a trivial instrumented function, with a number of tracers enabled with relevant filters (which would apply to the instrumented function) and a number of tracers enabled with irrelevant filters (which would not apply to the instrumented function). I tested on an M1 MacBook Pro, running under a HVF-accelerated QEMU VM (i.e. on real hardware). Before this patch: Number of tracers || Total time | Per-call average time (ns) Relevant | Irrelevant || (ns) | Total | Overhead =========+============++=============+==============+============ 0 | 0 || 94,583 | 0.95 | - 0 | 1 || 93,709 | 0.94 | - 0 | 2 || 93,666 | 0.94 | - 0 | 10 || 93,709 | 0.94 | - 0 | 100 || 93,792 | 0.94 | - ---------+------------++-------------+--------------+------------ 1 | 1 || 6,467,833 | 64.68 | 63.73 1 | 2 || 7,509,708 | 75.10 | 74.15 1 | 10 || 23,786,792 | 237.87 | 236.92 1 | 100 || 106,432,500 | 1,064.43 | 1063.38 ---------+------------++-------------+--------------+------------ 1 | 0 || 1,431,875 | 14.32 | 13.37 2 | 0 || 6,456,334 | 64.56 | 63.62 10 | 0 || 22,717,000 | 227.17 | 226.22 100 | 0 || 103,293,667 | 1032.94 | 1031.99 ---------+------------++-------------+--------------+-------------- Note: per-call overhead is estimated relative to the baseline case with 0 relevant tracers and 0 irrelevant tracers. After this patch Number of tracers || Total time | Per-call average time (ns) Relevant | Irrelevant || (ns) | Total | Overhead =========+============++=============+==============+============ 0 | 0 || 94,541 | 0.95 | - 0 | 1 || 93,666 | 0.94 | - 0 | 2 || 93,709 | 0.94 | - 0 | 10 || 93,667 | 0.94 | - 0 | 100 || 93,792 | 0.94 | - ---------+------------++-------------+--------------+------------ 1 | 1 || 281,000 | 2.81 | 1.86 1 | 2 || 281,042 | 2.81 | 1.87 1 | 10 || 280,958 | 2.81 | 1.86 1 | 100 || 281,250 | 2.81 | 1.87 ---------+------------++-------------+--------------+------------ 1 | 0 || 280,959 | 2.81 | 1.86 2 | 0 || 6,502,708 | 65.03 | 64.08 10 | 0 || 18,681,209 | 186.81 | 185.87 100 | 0 || 103,550,458 | 1,035.50 | 1034.56 ---------+------------++-------------+--------------+------------ Note: per-call overhead is estimated relative to the baseline case with 0 relevant tracers and 0 irrelevant tracers. As can be seen from the above: a) Whenever there is a single relevant tracer function associated with a tracee, the overhead of invoking the tracer is constant, and does not scale with the number of tracers which are *not* associated with that tracee. b) The overhead for a single relevant tracer has dropped to ~1/7 of the overhead prior to this series (from 13.37ns to 1.86ns). This is largely due to permitting calls to dynamically-allocated ftrace_ops without going through ftrace_ops_list_func. I've run the ftrace selftests from v6.2-rc3, which reports: | # of passed: 110 | # of failed: 0 | # of unresolved: 3 | # of untested: 0 | # of unsupported: 0 | # of xfailed: 1 | # of undefined(test bug): 0 ... where the unresolved entries were the tests for DIRECT functions (which are not supported), and the checkbashisms selftest (which is irrelevant here): | [8] Test ftrace direct functions against tracers [UNRESOLVED] | [9] Test ftrace direct functions against kprobes [UNRESOLVED] | [62] Meta-selftest: Checkbashisms [UNRESOLVED] ... with all other tests passing (or failing as expected). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Florent Revest <revest@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230123134603.1064407-9-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24arm64: ftrace: Update stale commentMark Rutland
In commit: 26299b3f6ba26bfc ("ftrace: arm64: move from REGS to ARGS") ... we folded ftrace_regs_entry into ftrace_caller, and ftrace_regs_entry no longer exists. Update the comment accordingly. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Florent Revest <revest@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230123134603.1064407-8-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-24arm64: patching: Add aarch64_insn_write_literal_u64()Mark Rutland
In subsequent patches we'll need to atomically write to a naturally-aligned 64-bit literal embedded within the kernel text. Add a helper for this. For consistency with other text patching code we use copy_to_kernel_nofault(), which is atomic for naturally-aligned accesses up to 64-bits. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Florent Revest <revest@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20230123134603.1064407-7-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-23Merge tag 'efi-fixes-for-v6.2-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI fixes from Ard Biesheuvel: "Another couple of EFI fixes, of which the first two were already in -next when I sent out the previous PR, but they caused some issues on non-EFI boots so I let them simmer for a bit longer. - ensure the EFI ResetSystem and ACPI PRM calls are recognized as users of the EFI runtime, and therefore protected against exceptions - account for the EFI runtime stack in the stacktrace code - remove Matthew Garrett's MAINTAINERS entry for efivarfs" * tag 'efi-fixes-for-v6.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi: Remove Matthew Garrett as efivarfs maintainer arm64: efi: Account for the EFI runtime stack in stack unwinder arm64: efi: Avoid workqueue to check whether EFI runtime is live
2023-01-22Merge 6.2-rc5 into driver-core-nextGreg Kroah-Hartman
We need the driver core fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-20arm64: cpufeature: Use kstrtobool() instead of strtobool()Christophe JAILLET
strtobool() is the same as kstrtobool(). However, the latter is more used within the kernel. In order to remove strtobool() and slightly simplify kstrtox.h, switch to the other function name. While at it, include the corresponding header file (<linux/kstrtox.h>) Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/5a1b329cda34aec67615c0d2fd326eb0d6634bf7.1667336095.git.christophe.jaillet@wanadoo.fr Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-20arm64: Add compat hwcap SSBSAmit Daniel Kachhap
This hwcap was added for 32-bit native arm kernel by commit fea53546be57 ("ARM: 9274/1: Add hwcap for Speculative Store Bypassing Safe") and hence the corresponding changes added in 32-bit compat arm64 for similar user interfaces. Speculative Store Bypass Safe is a feature(FEAT_SSBS) present in AArch32/AArch64 state for Armv8 and can be identified by PFR2.SSBS identification register. This hwcap is already advertised in native arm64 kernel. Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20230111053706.13994-8-amit.kachhap@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-20arm64: Add compat hwcap SBAmit Daniel Kachhap
This hwcap was added for 32-bit native arm kernel by commit 3bda6d884897 ("ARM: 9273/1: Add hwcap for Speculation Barrier(SB)") and hence the corresponding changes added in 32-bit compat arm64 kernel. Speculation Barrier is a feature(FEAT_SB) present in both AArch32 and AArch64 state. This hwcap is already advertised in native arm64 kernel. Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20230111053706.13994-7-amit.kachhap@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-20arm64: Add compat hwcap I8MMAmit Daniel Kachhap
This hwcap was added earlier for 32-bit native arm kernel by commit 956ca3a4eb81 ("ARM: 9272/1: vfp: Add hwcap for FEAT_AA32I8MM") and hence the corresponding changes added in 32-bit compat arm64 kernel for similar user interfaces. Int8 matrix multiplication is a feature (FEAT_AA32I8MM) present in AArch32 state of Armv8 and is identified by ISAR6.I8MM register. Similar feature(FEAT_I8MM) exist for AArch64 state and is already advertised in arm64 kernel. Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20230111053706.13994-6-amit.kachhap@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-01-20arm64: Add compat hwcap ASIMDBF16Amit Daniel Kachhap
This hwcap was added earlier for 32-bit native arm kernel by commit 23b6d4ad6e7a ("ARM: 9271/1: vfp: Add hwcap for FEAT_AA32BF16") and hence the corresponding changes added in 32-bit compat arm64 kernel. Brain 16-bit floating-point storage format is a feature (FEAT_AA32BF16) present in AArch32 state for Armv8 and is represented by ISAR6.BF16 identification register. Similar feature (FEAT_BF16) exist for AArch64 state and is already advertised in native arm64 kernel. Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20230111053706.13994-5-amit.kachhap@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>