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2021-07-14arm64/mm: Fix ttbr0 values stored in struct thread_info for software-panAnshuman Khandual
[ Upstream commit 9163f01130304fab1f74683d7d44632da7bda637 ] When using CONFIG_ARM64_SW_TTBR0_PAN, a task's thread_info::ttbr0 must be the TTBR0_EL1 value used to run userspace. With 52-bit PAs, the PA must be packed into the TTBR using phys_to_ttbr(), but we forget to do this in some of the SW PAN code. Thus, if the value is installed into TTBR0_EL1 (as may happen in the uaccess routines), this could result in UNPREDICTABLE behaviour. Since hardware with 52-bit PA support almost certainly has HW PAN, which will be used in preference, this shouldn't be a practical issue, but let's fix this for consistency. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Fixes: 529c4b05a3cb ("arm64: handle 52-bit addresses in TTBR") Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/1623749578-11231-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14arm64: perf: Convert snprintf to sysfs_emitTian Tao
[ Upstream commit a5740e955540181f4ab8f076cc9795c6bbe4d730 ] Use sysfs_emit instead of snprintf to avoid buf overrun,because in sysfs_emit it strictly checks whether buf is null or buf whether pagesize aligned, otherwise it returns an error. Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Link: https://lore.kernel.org/r/1621497585-30887-1-git-send-email-tiantao6@hisilicon.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14sched/core: Initialize the idle task with preemption disabledValentin Schneider
[ Upstream commit f1a0a376ca0c4ef1fc3d24e3e502acbb5b795674 ] As pointed out by commit de9b8f5dcbd9 ("sched: Fix crash trying to dequeue/enqueue the idle thread") init_idle() can and will be invoked more than once on the same idle task. At boot time, it is invoked for the boot CPU thread by sched_init(). Then smp_init() creates the threads for all the secondary CPUs and invokes init_idle() on them. As the hotplug machinery brings the secondaries to life, it will issue calls to idle_thread_get(), which itself invokes init_idle() yet again. In this case it's invoked twice more per secondary: at _cpu_up(), and at bringup_cpu(). Given smp_init() already initializes the idle tasks for all *possible* CPUs, no further initialization should be required. Now, removing init_idle() from idle_thread_get() exposes some interesting expectations with regards to the idle task's preempt_count: the secondary startup always issues a preempt_disable(), requiring some reset of the preempt count to 0 between hot-unplug and hotplug, which is currently served by idle_thread_get() -> idle_init(). Given the idle task is supposed to have preemption disabled once and never see it re-enabled, it seems that what we actually want is to initialize its preempt_count to PREEMPT_DISABLED and leave it there. Do that, and remove init_idle() from idle_thread_get(). Secondary startups were patched via coccinelle: @begone@ @@ -preempt_disable(); ... cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20210512094636.2958515-1-valentin.schneider@arm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19arm64: entry: always set GIC_PRIO_PSR_I_SET during entrySasha Levin
[ Upstream commit 4d6a38da8e79e94cbd1344aa90876f0f805db705 ] Zenghui reports that booting a kernel with "irqchip.gicv3_pseudo_nmi=1" on the command line hits a warning during kernel entry, due to the way we manipulate the PMR. Early in the entry sequence, we call lockdep_hardirqs_off() to inform lockdep that interrupts have been masked (as the HW sets DAIF wqhen entering an exception). Architecturally PMR_EL1 is not affected by exception entry, and we don't set GIC_PRIO_PSR_I_SET in the PMR early in the exception entry sequence, so early in exception entry the PMR can indicate that interrupts are unmasked even though they are masked by DAIF. If DEBUG_LOCKDEP is selected, lockdep_hardirqs_off() will check that interrupts are masked, before we set GIC_PRIO_PSR_I_SET in any of the exception entry paths, and hence lockdep_hardirqs_off() will WARN() that something is amiss. We can avoid this by consistently setting GIC_PRIO_PSR_I_SET during exception entry so that kernel code sees a consistent environment. We must also update local_daif_inherit() to undo this, as currently only touches DAIF. For other paths, local_daif_restore() will update both DAIF and the PMR. With this done, we can remove the existing special cases which set this later in the entry code. We always use (GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET) for consistency with local_daif_save(), as this will warn if it ever encounters (GIC_PRIO_IRQOFF | GIC_PRIO_PSR_I_SET), and never sets this itself. This matches the gic_prio_kentry_setup that we have to retain for ret_to_user. The original splat from Zenghui's report was: | DEBUG_LOCKS_WARN_ON(!irqs_disabled()) | WARNING: CPU: 3 PID: 125 at kernel/locking/lockdep.c:4258 lockdep_hardirqs_off+0xd4/0xe8 | Modules linked in: | CPU: 3 PID: 125 Comm: modprobe Tainted: G W 5.12.0-rc8+ #463 | Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 | pstate: 604003c5 (nZCv DAIF +PAN -UAO -TCO BTYPE=--) | pc : lockdep_hardirqs_off+0xd4/0xe8 | lr : lockdep_hardirqs_off+0xd4/0xe8 | sp : ffff80002a39bad0 | pmr_save: 000000e0 | x29: ffff80002a39bad0 x28: ffff0000de214bc0 | x27: ffff0000de1c0400 x26: 000000000049b328 | x25: 0000000000406f30 x24: ffff0000de1c00a0 | x23: 0000000020400005 x22: ffff8000105f747c | x21: 0000000096000044 x20: 0000000000498ef9 | x19: ffff80002a39bc88 x18: ffffffffffffffff | x17: 0000000000000000 x16: ffff800011c61eb0 | x15: ffff800011700a88 x14: 0720072007200720 | x13: 0720072007200720 x12: 0720072007200720 | x11: 0720072007200720 x10: 0720072007200720 | x9 : ffff80002a39bad0 x8 : ffff80002a39bad0 | x7 : ffff8000119f0800 x6 : c0000000ffff7fff | x5 : ffff8000119f07a8 x4 : 0000000000000001 | x3 : 9bcdab23f2432800 x2 : ffff800011730538 | x1 : 9bcdab23f2432800 x0 : 0000000000000000 | Call trace: | lockdep_hardirqs_off+0xd4/0xe8 | enter_from_kernel_mode.isra.5+0x7c/0xa8 | el1_abort+0x24/0x100 | el1_sync_handler+0x80/0xd0 | el1_sync+0x6c/0x100 | __arch_clear_user+0xc/0x90 | load_elf_binary+0x9fc/0x1450 | bprm_execve+0x404/0x880 | kernel_execve+0x180/0x188 | call_usermodehelper_exec_async+0xdc/0x158 | ret_from_fork+0x10/0x18 Fixes: 23529049c684 ("arm64: entry: fix non-NMI user<->kernel transitions") Fixes: 7cd1ea1010ac ("arm64: entry: fix non-NMI kernel<->kernel transitions") Fixes: f0cd5ac1e4c5 ("arm64: entry: fix NMI {user, kernel}->kernel transitions") Fixes: 2a9b3e6ac69a ("arm64: entry: fix EL1 debug transitions") Link: https://lore.kernel.org/r/f4012761-026f-4e51-3a0c-7524e434e8b3@huawei.com Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reported-by: Zenghui Yu <yuzenghui@huawei.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Will Deacon <will@kernel.org> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210428111555.50880-1-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19arm64: entry: factor irq triage logic into macrosMarc Zyngier
[ Upstream commit 9eb563cdabe1d583c262042d5d44cc256f644543 ] In subsequent patches we'll allow an FIQ handler to be registered, and FIQ exceptions will need to be triaged very similarly to IRQ exceptions. So that we can reuse the existing logic, this patch factors the IRQ triage logic out into macros that can be reused for FIQ. The macros are named to follow the elX_foo_handler scheme used by the C exception handlers. For consistency with other top-level exception handlers, the kernel_entry/kernel_exit logic is not moved into the macros. As FIQ will use a different C handler, this handler name is provided as an argument to the macros. There should be no functional change as a result of this patch. Signed-off-by: Marc Zyngier <maz@kernel.org> [Mark: rework macros, commit message, rebase before DAIF rework] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Hector Martin <marcan@marcan.st> Cc: James Morse <james.morse@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210315115629.57191-5-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19arm64: stacktrace: restore terminal recordsMark Rutland
[ Upstream commit 8533d5bfad41e74b7dd80d292fd484913cdfb374 ] We removed the terminal frame records in commit: 6106e1112cc69a36 ("arm64: remove EL0 exception frame record") ... on the assumption that as we no longer used them to find the pt_regs at exception boundaries, they were no longer necessary. However, Leo reports that as an unintended side-effect, this causes traces which cross secondary_start_kernel to terminate one entry too late, with a spurious "0" entry. There are a few ways we could sovle this, but as we're planning to use terminal records for RELIABLE_STACKTRACE, let's revert the logic change for now, keeping the update comments and accounting for the changes in commit: 3c02600144bdb0a1 ("arm64: stacktrace: Report when we reach the end of the stack") This is effectively a partial revert of commit: 6106e1112cc69a36 ("arm64: remove EL0 exception frame record") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Fixes: 6106e1112cc6 ("arm64: remove EL0 exception frame record") Reported-by: Leo Yan <leo.yan@linaro.org> Tested-by: Leo Yan <leo.yan@linaro.org> Cc: Will Deacon <will@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com> Link: https://lore.kernel.org/r/20210429104813.GA33550@C02TD0UTHF1T.local Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-12arm64/vdso: Discard .note.gnu.property sections in vDSOBill Wendling
[ Upstream commit 388708028e6937f3fc5fc19aeeb847f8970f489c ] The arm64 assembler in binutils 2.32 and above generates a program property note in a note section, .note.gnu.property, to encode used x86 ISAs and features. But the kernel linker script only contains a single NOTE segment: PHDRS { text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ note PT_NOTE FLAGS(4); /* PF_R */ } The NOTE segment generated by the vDSO linker script is aligned to 4 bytes. But the .note.gnu.property section must be aligned to 8 bytes on arm64. $ readelf -n vdso64.so Displaying notes found in: .note Owner Data size Description Linux 0x00000004 Unknown note type: (0x00000000) description data: 06 00 00 00 readelf: Warning: note with invalid namesz and/or descsz found at offset 0x20 readelf: Warning: type: 0x78, namesize: 0x00000100, descsize: 0x756e694c, alignment: 8 Since the note.gnu.property section in the vDSO is not checked by the dynamic linker, discard the .note.gnu.property sections in the vDSO. Similar to commit 4caffe6a28d31 ("x86/vdso: Discard .note.gnu.property sections in vDSO"), but for arm64. Signed-off-by: Bill Wendling <morbo@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20210423205159.830854-1-morbo@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-16kasan: remove redundant config optionWalter Wu
CONFIG_KASAN_STACK and CONFIG_KASAN_STACK_ENABLE both enable KASAN stack instrumentation, but we should only need one config, so that we remove CONFIG_KASAN_STACK_ENABLE and make CONFIG_KASAN_STACK workable. see [1]. When enable KASAN stack instrumentation, then for gcc we could do no prompt and default value y, and for clang prompt and default value n. This patch fixes the following compilation warning: include/linux/kasan.h:333:30: warning: 'CONFIG_KASAN_STACK' is not defined, evaluates to 0 [-Wundef] [akpm@linux-foundation.org: fix merge snafu] Link: https://bugzilla.kernel.org/show_bug.cgi?id=210221 [1] Link: https://lkml.kernel.org/r/20210226012531.29231-1-walter-zh.wu@mediatek.com Fixes: d9b571c885a8 ("kasan: fix KASAN_STACK dependency for HW_TAGS") Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com> Suggested-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-14Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: - Fix incorrect asm constraint for load_unaligned_zeropad() fixup - Fix thread flag update when setting TIF_MTE_ASYNC_FAULT - Fix restored irq state when handling fault on kprobe * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: kprobes: Restore local irqflag if kprobes is cancelled arm64: mte: Ensure TIF_MTE_ASYNC_FAULT is set atomically arm64: fix inline asm in load_unaligned_zeropad()
2021-04-13arm64: kprobes: Restore local irqflag if kprobes is cancelledJisheng Zhang
If instruction being single stepped caused a page fault, the kprobes is cancelled to let the page fault handler continue as a normal page fault. But the local irqflags are disabled so cpu will restore pstate with DAIF masked. After pagefault is serviced, the kprobes is triggerred again, we overwrite the saved_irqflag by calling kprobes_save_local_irqflag(). NOTE, DAIF is masked in this new saved irqflag. After kprobes is serviced, the cpu pstate is retored with DAIF masked. This patch is inspired by one patch for riscv from Liao Chang. Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20210412174101.6bfb0594@xhacker.debian Signed-off-by: Will Deacon <will@kernel.org>
2021-04-12arm64: mte: Ensure TIF_MTE_ASYNC_FAULT is set atomicallyCatalin Marinas
The entry from EL0 code checks the TFSRE0_EL1 register for any asynchronous tag check faults in user space and sets the TIF_MTE_ASYNC_FAULT flag. This is not done atomically, potentially racing with another CPU calling set_tsk_thread_flag(). Replace the non-atomic ORR+STR with an STSET instruction. While STSET requires ARMv8.1 and an assembler that understands LSE atomics, the MTE feature is part of ARMv8.5 and already requires an updated assembler. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Fixes: 637ec831ea4f ("arm64: mte: Handle synchronous and asynchronous tag check faults") Cc: <stable@vger.kernel.org> # 5.10.x Reported-by: Will Deacon <will@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20210409173710.18582-1-catalin.marinas@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-03-30Merge tag 'kvmarm-fixes-5.12-3' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.12, take #3 - Fix GICv3 MMIO compatibility probing - Prevent guests from using the ARMv8.4 self-hosted tracing extension
2021-03-25Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "Minor fixes all over, ranging from typos to tests to errata workarounds: - Fix possible memory hotplug failure with KASLR - Fix FFR value in SVE kselftest - Fix backtraces reported in /proc/$pid/stack - Disable broken CnP implementation on NVIDIA Carmel - Typo fixes and ACPI documentation clarification - Fix some W=1 warnings" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: kernel: disable CNP on Carmel arm64/process.c: fix Wmissing-prototypes build warnings kselftest/arm64: sve: Do not use non-canonical FFR register value arm64: mm: correct the inside linear map range during hotplug check arm64: kdump: update ppos when reading elfcorehdr arm64: cpuinfo: Fix a typo Documentation: arm64/acpi : clarify arm64 support of IBFT arm64: stacktrace: don't trace arch_stack_walk() arm64: csum: cast to the proper type
2021-03-25arm64: kernel: disable CNP on CarmelRich Wiley
On NVIDIA Carmel cores, CNP behaves differently than it does on standard ARM cores. On Carmel, if two cores have CNP enabled and share an L2 TLB entry created by core0 for a specific ASID, a non-shareable TLBI from core1 may still see the shared entry. On standard ARM cores, that TLBI will invalidate the shared entry as well. This causes issues with patchsets that attempt to do local TLBIs based on cpumasks instead of broadcast TLBIs. Avoid these issues by disabling CNP support for NVIDIA Carmel cores. Signed-off-by: Rich Wiley <rwiley@nvidia.com> Link: https://lore.kernel.org/r/20210324002809.30271-1-rwiley@nvidia.com [will: Fix pre-existing whitespace issue] Signed-off-by: Will Deacon <will@kernel.org>
2021-03-25arm64/process.c: fix Wmissing-prototypes build warningsManinder Singh
Fix GCC warnings reported when building with "-Wmissing-prototypes": arch/arm64/kernel/process.c:261:6: warning: no previous prototype for '__show_regs' [-Wmissing-prototypes] 261 | void __show_regs(struct pt_regs *regs) | ^~~~~~~~~~~ arch/arm64/kernel/process.c:307:6: warning: no previous prototype for '__show_regs_alloc_free' [-Wmissing-prototypes] 307 | void __show_regs_alloc_free(struct pt_regs *regs) | ^~~~~~~~~~~~~~~~~~~~~~ arch/arm64/kernel/process.c:365:5: warning: no previous prototype for 'arch_dup_task_struct' [-Wmissing-prototypes] 365 | int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) | ^~~~~~~~~~~~~~~~~~~~ arch/arm64/kernel/process.c:546:41: warning: no previous prototype for '__switch_to' [-Wmissing-prototypes] 546 | __notrace_funcgraph struct task_struct *__switch_to(struct task_struct *prev, | ^~~~~~~~~~~ arch/arm64/kernel/process.c:710:25: warning: no previous prototype for 'arm64_preempt_schedule_irq' [-Wmissing-prototypes] 710 | asmlinkage void __sched arm64_preempt_schedule_irq(void) | ^~~~~~~~~~~~~~~~~~~~~~~~~~ Link: https://lore.kernel.org/lkml/202103192250.AennsfXM-lkp@intel.com Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Link: https://lore.kernel.org/r/1616568899-986-1-git-send-email-maninder1.s@samsung.com Signed-off-by: Will Deacon <will@kernel.org>
2021-03-24KVM: arm64: Hide system instruction access to Trace registersSuzuki K Poulose
Currently we advertise the ID_AA6DFR0_EL1.TRACEVER for the guest, when the trace register accesses are trapped (CPTR_EL2.TTA == 1). So, the guest will get an undefined instruction, if trusts the ID registers and access one of the trace registers. Lets be nice to the guest and hide the feature to avoid unexpected behavior. Even though this can be done at KVM sysreg emulation layer, we do this by removing the TRACEVER from the sanitised feature register field. This is fine as long as the ETM drivers can handle the individual trace units separately, even when there are differences among the CPUs. Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210323120647.454211-2-suzuki.poulose@arm.com
2021-03-22arm64: kdump: update ppos when reading elfcorehdrPavel Tatashin
The ppos points to a position in the old kernel memory (and in case of arm64 in the crash kernel since elfcorehdr is passed as a segment). The function should update the ppos by the amount that was read. This bug is not exposed by accident, but other platforms update this value properly. So, fix it in ARM64 version of elfcorehdr_read() as well. Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> Fixes: e62aaeac426a ("arm64: kdump: provide /proc/vmcore file") Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com> Link: https://lore.kernel.org/r/20210319205054.743368-1-pasha.tatashin@soleen.com Signed-off-by: Will Deacon <will@kernel.org>
2021-03-22arm64: cpuinfo: Fix a typoBhaskar Chowdhury
s/acurate/accurate/ Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20210319222848.29928-1-unixbhaskar@gmail.com Signed-off-by: Will Deacon <will@kernel.org>
2021-03-22arm64: stacktrace: don't trace arch_stack_walk()Mark Rutland
We recently converted arm64 to use arch_stack_walk() in commit: 5fc57df2f6fd ("arm64: stacktrace: Convert to ARCH_STACKWALK") The core stacktrace code expects that (when tracing the current task) arch_stack_walk() starts a trace at its caller, and does not include itself in the trace. However, arm64's arch_stack_walk() includes itself, and so traces include one more entry than callers expect. The core stacktrace code which calls arch_stack_walk() tries to skip a number of entries to prevent itself appearing in a trace, and the additional entry prevents skipping one of the core stacktrace functions, leaving this in the trace unexpectedly. We can fix this by having arm64's arch_stack_walk() begin the trace with its caller. The first value returned by the trace will be __builtin_return_address(0), i.e. the caller of arch_stack_walk(). The first frame record to be unwound will be __builtin_frame_address(1), i.e. the caller's frame record. To prevent surprises, arch_stack_walk() is also marked noinline. While __builtin_frame_address(1) is not safe in portable code, local GCC developers have confirmed that it is safe on arm64. To find the caller's frame record, the builtin can safely dereference the current function's frame record or (in theory) could stash the original FP into another GPR at function entry time, neither of which are problematic. Prior to this patch, the tracing code would unexpectedly show up in traces of the current task, e.g. | # cat /proc/self/stack | [<0>] stack_trace_save_tsk+0x98/0x100 | [<0>] proc_pid_stack+0xb4/0x130 | [<0>] proc_single_show+0x60/0x110 | [<0>] seq_read_iter+0x230/0x4d0 | [<0>] seq_read+0xdc/0x130 | [<0>] vfs_read+0xac/0x1e0 | [<0>] ksys_read+0x6c/0xfc | [<0>] __arm64_sys_read+0x20/0x30 | [<0>] el0_svc_common.constprop.0+0x60/0x120 | [<0>] do_el0_svc+0x24/0x90 | [<0>] el0_svc+0x2c/0x54 | [<0>] el0_sync_handler+0x1a4/0x1b0 | [<0>] el0_sync+0x170/0x180 After this patch, the tracing code will not show up in such traces: | # cat /proc/self/stack | [<0>] proc_pid_stack+0xb4/0x130 | [<0>] proc_single_show+0x60/0x110 | [<0>] seq_read_iter+0x230/0x4d0 | [<0>] seq_read+0xdc/0x130 | [<0>] vfs_read+0xac/0x1e0 | [<0>] ksys_read+0x6c/0xfc | [<0>] __arm64_sys_read+0x20/0x30 | [<0>] el0_svc_common.constprop.0+0x60/0x120 | [<0>] do_el0_svc+0x24/0x90 | [<0>] el0_svc+0x2c/0x54 | [<0>] el0_sync_handler+0x1a4/0x1b0 | [<0>] el0_sync+0x170/0x180 Erring on the side of caution, I've given this a spin with a bunch of toolchains, verifying the output of /proc/self/stack and checking that the assembly looked sound. For GCC (where we require version 5.1.0 or later) I tested with the kernel.org crosstool binares for versions 5.5.0, 6.4.0, 6.5.0, 7.3.0, 7.5.0, 8.1.0, 8.3.0, 8.4.0, 9.2.0, and 10.1.0. For clang (where we require version 10.0.1 or later) I tested with the llvm.org binary releases of 11.0.0, and 11.0.1. Fixes: 5fc57df2f6fd ("arm64: stacktrace: Convert to ARCH_STACKWALK") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Jun <chenjun102@huawei.com> Cc: Marco Elver <elver@google.com> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: <stable@vger.kernel.org> # 5.10.x Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20210319184106.5688-1-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-03-14Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "More fixes for ARM and x86" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: LAPIC: Advancing the timer expiration on guest initiated write KVM: x86/mmu: Skip !MMU-present SPTEs when removing SP in exclusive mode KVM: kvmclock: Fix vCPUs > 64 can't be online/hotpluged kvm: x86: annotate RCU pointers KVM: arm64: Fix exclusive limit for IPA size KVM: arm64: Reject VM creation when the default IPA size is unsupported KVM: arm64: Ensure I-cache isolation between vcpus of a same VM KVM: arm64: Don't use cbz/adr with external symbols KVM: arm64: Fix range alignment when walking page tables KVM: arm64: Workaround firmware wrongly advertising GICv2-on-v3 compatibility KVM: arm64: Rename __vgic_v3_get_ich_vtr_el2() to __vgic_v3_get_gic_config() KVM: arm64: Don't access PMSELR_EL0/PMUSERENR_EL0 when no PMU is available KVM: arm64: Turn kvm_arm_support_pmu_v3() into a static key KVM: arm64: Fix nVHE hyp panic host context restore KVM: arm64: Avoid corrupting vCPU context register in guest exit KVM: arm64: nvhe: Save the SPE context early kvm: x86: use NULL instead of using plain integer as pointer KVM: SVM: Connect 'npt' module param to KVM's internal 'npt_enabled' KVM: x86: Ensure deadline timer has truly expired before posting its IRQ
2021-03-11arm64: mm: use a 48-bit ID map when possible on 52-bit VA buildsArd Biesheuvel
52-bit VA kernels can run on hardware that is only 48-bit capable, but configure the ID map as 52-bit by default. This was not a problem until recently, because the special T0SZ value for a 52-bit VA space was never programmed into the TCR register anwyay, and because a 52-bit ID map happens to use the same number of translation levels as a 48-bit one. This behavior was changed by commit 1401bef703a4 ("arm64: mm: Always update TCR_EL1 from __cpu_set_tcr_t0sz()"), which causes the unsupported T0SZ value for a 52-bit VA to be programmed into TCR_EL1. While some hardware simply ignores this, Mark reports that Amberwing systems choke on this, resulting in a broken boot. But even before that commit, the unsupported idmap_t0sz value was exposed to KVM and used to program TCR_EL2 incorrectly as well. Given that we already have to deal with address spaces being either 48-bit or 52-bit in size, the cleanest approach seems to be to simply default to a 48-bit VA ID map, and only switch to a 52-bit one if the placement of the kernel in DRAM requires it. This is guaranteed not to happen unless the system is actually 52-bit VA capable. Fixes: 90ec95cda91a ("arm64: mm: Introduce VA_BITS_MIN") Reported-by: Mark Salter <msalter@redhat.com> Link: http://lore.kernel.org/r/20210310003216.410037-1-msalter@redhat.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20210310171515.416643-2-ardb@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-03-10arm64: perf: Fix 64-bit event counter read truncationRob Herring
Commit 0fdf1bb75953 ("arm64: perf: Avoid PMXEV* indirection") changed armv8pmu_read_evcntr() to return a u32 instead of u64. The result is silent truncation of the event counter when using 64-bit counters. Given the offending commit appears to have passed thru several folks, it seems likely this was a bad rebase after v8.5 PMU 64-bit counters landed. Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Julien Thierry <julien.thierry.kdev@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: <stable@vger.kernel.org> Fixes: 0fdf1bb75953 ("arm64: perf: Avoid PMXEV* indirection") Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Link: https://lore.kernel.org/r/20210310004412.1450128-1-robh@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-03-10arm64/mm: Fix __enable_mmu() for new TGRAN range valuesJames Morse
As per ARM ARM DDI 0487G.a, when FEAT_LPA2 is implemented, ID_AA64MMFR0_EL1 might contain a range of values to describe supported translation granules (4K and 16K pages sizes in particular) instead of just enabled or disabled values. This changes __enable_mmu() function to handle complete acceptable range of values (depending on whether the field is signed or unsigned) now represented with ID_AA64MMFR0_TGRAN_SUPPORTED_[MIN..MAX] pair. While here, also fix similar situations in EFI stub and KVM as well. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: kvmarm@lists.cs.columbia.edu Cc: linux-efi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Acked-by: Marc Zyngier <maz@kernel.org> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/1615355590-21102-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-03-08arm64: Drop support for CMDLINE_EXTENDWill Deacon
The documented behaviour for CMDLINE_EXTEND is that the arguments from the bootloader are appended to the built-in kernel command line. This also matches the option parsing behaviour for the EFI stub and early ID register overrides. Bizarrely, the fdt behaviour is the other way around: appending the built-in command line to the bootloader arguments, resulting in a command-line that doesn't necessarily line-up with the parsing order and definitely doesn't line-up with the documented behaviour. As it turns out, there is a proposal [1] to replace CMDLINE_EXTEND with CMDLINE_PREPEND and CMDLINE_APPEND options which should hopefully make the intended behaviour much clearer. While we wait for those to land, drop CMDLINE_EXTEND for now as there appears to be little enthusiasm for changing the current FDT behaviour. [1] https://lore.kernel.org/lkml/20190319232448.45964-2-danielwa@cisco.com/ Cc: Max Uvarov <muvarov@gmail.com> Cc: Rob Herring <robh@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Doug Anderson <dianders@chromium.org> Cc: Tyler Hicks <tyhicks@linux.microsoft.com> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/CAL_JsqJX=TCCs7=gg486r9TN4NYscMTCLNfqJF9crskKPq-bTg@mail.gmail.com Link: https://lore.kernel.org/r/20210303134927.18975-3-will@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-03-08arm64: cpufeatures: Fix handling of CONFIG_CMDLINE for idreg overridesWill Deacon
The built-in kernel commandline (CONFIG_CMDLINE) can be configured in three different ways: 1. CMDLINE_FORCE: Use CONFIG_CMDLINE instead of any bootloader args 2. CMDLINE_EXTEND: Append the bootloader args to CONFIG_CMDLINE 3. CMDLINE_FROM_BOOTLOADER: Only use CONFIG_CMDLINE if there aren't any bootloader args. The early cmdline parsing to detect idreg overrides gets (2) and (3) slightly wrong: in the case of (2) the bootloader args are parsed first and in the case of (3) the CMDLINE is always parsed. Fix these issues by moving the bootargs parsing out into a helper function and following the same logic as that used by the EFI stub. Reviewed-by: Marc Zyngier <maz@kernel.org> Fixes: 33200303553d ("arm64: cpufeature: Add an early command-line cpufeature override facility") Link: https://lore.kernel.org/r/20210303134927.18975-2-will@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-03-06KVM: arm64: Don't access PMSELR_EL0/PMUSERENR_EL0 when no PMU is availableMarc Zyngier
When running under a nesting hypervisor, it isn't guaranteed that the virtual HW will include a PMU. In which case, let's not try to access the PMU registers in the world switch, as that'd be deadly. Reported-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Link: https://lore.kernel.org/r/20210209114844.3278746-3-maz@kernel.org Message-Id: <20210305185254.3730990-6-maz@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-27Merge tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull io_uring thread rewrite from Jens Axboe: "This converts the io-wq workers to be forked off the tasks in question instead of being kernel threads that assume various bits of the original task identity. This kills > 400 lines of code from io_uring/io-wq, and it's the worst part of the code. We've had several bugs in this area, and the worry is always that we could be missing some pieces for file types doing unusual things (recent /dev/tty example comes to mind, userfaultfd reads installing file descriptors is another fun one... - both of which need special handling, and I bet it's not the last weird oddity we'll find). With these identical workers, we can have full confidence that we're never missing anything. That, in itself, is a huge win. Outside of that, it's also more efficient since we're not wasting space and code on tracking state, or switching between different states. I'm sure we're going to find little things to patch up after this series, but testing has been pretty thorough, from the usual regression suite to production. Any issue that may crop up should be manageable. There's also a nice series of further reductions we can do on top of this, but I wanted to get the meat of it out sooner rather than later. The general worry here isn't that it's fundamentally broken. Most of the little issues we've found over the last week have been related to just changes in how thread startup/exit is done, since that's the main difference between using kthreads and these kinds of threads. In fact, if all goes according to plan, I want to get this into the 5.10 and 5.11 stable branches as well. That said, the changes outside of io_uring/io-wq are: - arch setup, simple one-liner to each arch copy_thread() implementation. - Removal of net and proc restrictions for io_uring, they are no longer needed or useful" * tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block: (30 commits) io-wq: remove now unused IO_WQ_BIT_ERROR io_uring: fix SQPOLL thread handling over exec io-wq: improve manager/worker handling over exec io_uring: ensure SQPOLL startup is triggered before error shutdown io-wq: make buffered file write hashed work map per-ctx io-wq: fix race around io_worker grabbing io-wq: fix races around manager/worker creation and task exit io_uring: ensure io-wq context is always destroyed for tasks arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread() io_uring: cleanup ->user usage io-wq: remove nr_process accounting io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS net: remove cmsg restriction from io_uring based send/recvmsg calls Revert "proc: don't allow async path resolution of /proc/self components" Revert "proc: don't allow async path resolution of /proc/thread-self components" io_uring: move SQPOLL thread io-wq forked worker io-wq: make io_wq_fork_thread() available to other users io-wq: only remove worker from free_list, if it was there io_uring: remove io_identity io_uring: remove any grabbing of context ...
2021-02-26Merge tag 'riscv-for-linus-5.12-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: "A handful of new RISC-V related patches for this merge window: - A check to ensure drivers are properly using uaccess. This isn't manifesting with any of the drivers I'm currently using, but may catch errors in new drivers. - Some preliminary support for the FU740, along with the HiFive Unleashed it will appear on. - NUMA support for RISC-V, which involves making the arm64 code generic. - Support for kasan on the vmalloc region. - A handful of new drivers for the Kendryte K210, along with the DT plumbing required to boot on a handful of K210-based boards. - Support for allocating ASIDs. - Preliminary support for kernels larger than 128MiB. - Various other improvements to our KASAN support, including the utilization of huge pages when allocating the KASAN regions. We may have already found a bug with the KASAN_VMALLOC code, but it's passing my tests. There's a fix in the works, but that will probably miss the merge window. * tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (75 commits) riscv: Improve kasan population by using hugepages when possible riscv: Improve kasan population function riscv: Use KASAN_SHADOW_INIT define for kasan memory initialization riscv: Improve kasan definitions riscv: Get rid of MAX_EARLY_MAPPING_SIZE soc: canaan: Sort the Makefile alphabetically riscv: Disable KSAN_SANITIZE for vDSO riscv: Remove unnecessary declaration riscv: Add Canaan Kendryte K210 SD card defconfig riscv: Update Canaan Kendryte K210 defconfig riscv: Add Kendryte KD233 board device tree riscv: Add SiPeed MAIXDUINO board device tree riscv: Add SiPeed MAIX GO board device tree riscv: Add SiPeed MAIX DOCK board device tree riscv: Add SiPeed MAIX BiT board device tree riscv: Update Canaan Kendryte K210 device tree dt-bindings: add resets property to dw-apb-timer dt-bindings: fix sifive gpio properties dt-bindings: update sifive uart compatible string dt-bindings: update sifive clint compatible string ...
2021-02-26Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "The big one is a fix for the VHE enabling path during early boot, where the code enabling the MMU wasn't necessarily in the identity map of the new page-tables, resulting in a consistent crash with 64k pages. In fixing that, we noticed some missing barriers too, so we added those for the sake of architectural compliance. Other than that, just the usual merge window trickle. There'll be more to come, too. Summary: - Fix lockdep false alarm on resume-from-cpuidle path - Fix memory leak in kexec_file - Fix module linker script to work with GDB - Fix error code when trying to use uprobes with AArch32 instructions - Fix late VHE enabling with 64k pages - Add missing ISBs after TLB invalidation - Fix seccomp when tracing syscall -1 - Fix stacktrace return code at end of stack - Fix inconsistent whitespace for pointer return values - Fix compiler warnings when building with W=1" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: stacktrace: Report when we reach the end of the stack arm64: ptrace: Fix seccomp of traced syscall -1 (NO_SYSCALL) arm64: Add missing ISB after invalidating TLB in enter_vhe arm64: Add missing ISB after invalidating TLB in __primary_switch arm64: VHE: Enable EL2 MMU from the idmap KVM: arm64: make the hyp vector table entries local arm64/mm: Fixed some coding style issues arm64: uprobe: Return EOPNOTSUPP for AARCH32 instruction probing kexec: move machine_kexec_post_load() to public interface arm64 module: set plt* section addresses to 0x0 arm64: kexec_file: fix memory leakage in create_dtb() when fdt_open_into() fails arm64: spectre: Prevent lockdep splat on v4 mitigation enable path
2021-02-26arm64: kasan: simplify and inline MTE functionsAndrey Konovalov
This change provides a simpler implementation of mte_get_mem_tag(), mte_get_random_tag(), and mte_set_mem_tag_range(). Simplifications include removing system_supports_mte() checks as these functions are onlye called from KASAN runtime that had already checked system_supports_mte(). Besides that, size and address alignment checks are removed from mte_set_mem_tag_range(), as KASAN now does those. This change also moves these functions into the asm/mte-kasan.h header and implements mte_set_mem_tag_range() via inline assembly to avoid unnecessary functions calls. [vincenzo.frascino@arm.com: fix warning in mte_get_random_tag()] Link: https://lkml.kernel.org/r/20210211152208.23811-1-vincenzo.frascino@arm.com Link: https://lkml.kernel.org/r/a26121b294fdf76e369cb7a74351d1c03a908930.1612546384.git.andreyknvl@google.com Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Marco Elver <elver@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-25arm64: stacktrace: Report when we reach the end of the stackMark Brown
Currently the arm64 unwinder code returns -EINVAL whenever it can't find the next stack frame, not distinguishing between cases where the stack has been corrupted or is otherwise in a state it shouldn't be and cases where we have reached the end of the stack. At the minute none of the callers care what error code is returned but this will be important for reliable stack trace which needs to be sure that the stack is intact. Change to return -ENOENT in the case where we reach the bottom of the stack. The error codes from this function are only used in kernel, this particular code is chosen as we are indicating that we know there is no frame there. Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20210224165037.24138-1-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-02-25arm64: ptrace: Fix seccomp of traced syscall -1 (NO_SYSCALL)Timothy E Baldwin
Since commit f086f67485c5 ("arm64: ptrace: add support for syscall emulation"), if system call number -1 is called and the process is being traced with PTRACE_SYSCALL, for example by strace, the seccomp check is skipped and -ENOSYS is returned unconditionally (unless altered by the tracer) rather than carrying out action specified in the seccomp filter. The consequence of this is that it is not possible to reliably strace a seccomp based implementation of a foreign system call interface in which r7/x8 is permitted to be -1 on entry to a system call. Also trace_sys_enter and audit_syscall_entry are skipped if a system call is skipped. Fix by removing the in_syscall(regs) check restoring the previous behaviour which is like AArch32, x86 (which uses generic code) and everything else. Cc: Oleg Nesterov <oleg@redhat.com> Cc: Catalin Marinas<catalin.marinas@arm.com> Cc: <stable@vger.kernel.org> Fixes: f086f67485c5 ("arm64: ptrace: add support for syscall emulation") Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Timothy E Baldwin <T.E.Baldwin99@members.leeds.ac.uk> Link: https://lore.kernel.org/r/90edd33b-6353-1228-791f-0336d94d5f8c@majoroak.me.uk Signed-off-by: Will Deacon <will@kernel.org>
2021-02-24kasan, arm64: allow using KUnit tests with HW_TAGS modeAndrey Konovalov
On a high level, this patch allows running KUnit KASAN tests with the hardware tag-based KASAN mode. Internally, this change reenables tag checking at the end of each KASAN test that triggers a tag fault and leads to tag checking being disabled. Also simplify is_write calculation in report_tag_fault. With this patch KASAN tests are still failing for the hardware tag-based mode; fixes come in the next few patches. [andreyknvl@google.com: export HW_TAGS symbols for KUnit tests] Link: https://lkml.kernel.org/r/e7eeb252da408b08f0c81b950a55fb852f92000b.1613155970.git.andreyknvl@google.com Link: https://linux-review.googlesource.com/id/Id94dc9eccd33b23cda4950be408c27f879e474c8 Link: https://lkml.kernel.org/r/51b23112cf3fd62b8f8e9df81026fa2b15870501.1610733117.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Marco Elver <elver@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24arm64: Add missing ISB after invalidating TLB in enter_vheMarc Zyngier
Although there has been a bit of back and forth on the subject, it appears that invalidating TLBs requires an ISB instruction after the TLBI/DSB sequence when FEAT_ETS is not implemented by the CPU. From the bible: | In an implementation that does not implement FEAT_ETS, a TLB | maintenance instruction executed by a PE, PEx, can complete at any | time after it is issued, but is only guaranteed to be finished for a | PE, PEx, after the execution of DSB by the PEx followed by a Context | synchronization event Add the missing ISB in enter_vhe(), just in case. Fixes: f359182291c7 ("arm64: Provide an 'upgrade to VHE' stub hypercall") Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20210224093738.3629662-4-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-02-24arm64: Add missing ISB after invalidating TLB in __primary_switchMarc Zyngier
Although there has been a bit of back and forth on the subject, it appears that invalidating TLBs requires an ISB instruction when FEAT_ETS is not implemented by the CPU. From the bible: | In an implementation that does not implement FEAT_ETS, a TLB | maintenance instruction executed by a PE, PEx, can complete at any | time after it is issued, but is only guaranteed to be finished for a | PE, PEx, after the execution of DSB by the PEx followed by a Context | synchronization event Add the missing ISB in __primary_switch, just in case. Fixes: 3c5e9f238bc4 ("arm64: head.S: move KASLR processing out of __enable_mmu()") Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20210224093738.3629662-3-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-02-24arm64: VHE: Enable EL2 MMU from the idmapMarc Zyngier
Enabling the MMU requires the write to SCTLR_ELx (and the ISB that follows) to live in some identity-mapped memory. Otherwise, the translation will result in something totally unexpected (either fetching the wrong instruction stream, or taking a fault of some sort). This is exactly what happens in mutate_to_vhe(), as this code lives in the .hyp.text section, which isn't identity-mapped. With the right configuration, this explodes badly. Extract the MMU-enabling part of mutate_to_vhe(), and move it to its own function that lives in the idmap. This ensures nothing bad happens. Fixes: f359182291c7 ("arm64: Provide an 'upgrade to VHE' stub hypercall") Reported-by: "kernelci.org bot" <bot@kernelci.org> Tested-by: Guillaume Tucker <guillaume.tucker@collabora.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210224093738.3629662-2-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-02-23Merge tag 'clang-lto-v5.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull clang LTO updates from Kees Cook: "Clang Link Time Optimization. This is built on the work done preparing for LTO by arm64 folks, tracing folks, etc. This includes the core changes as well as the remaining pieces for arm64 (LTO has been the default build method on Android for about 3 years now, as it is the prerequisite for the Control Flow Integrity protections). While x86 LTO enablement is done, it depends on some pending objtool clean-ups. It's possible that I'll send a "part 2" pull request for LTO that includes x86 support. For merge log posterity, and as detailed in commit dc5723b02e52 ("kbuild: add support for Clang LTO"), here is the lt;dr to do an LTO build: make LLVM=1 LLVM_IAS=1 defconfig scripts/config -e LTO_CLANG_THIN make LLVM=1 LLVM_IAS=1 (To do a cross-compile of arm64, add "CROSS_COMPILE=aarch64-linux-gnu-" and "ARCH=arm64" to the "make" command lines.) Summary: - Clang LTO build infrastructure and arm64-specific enablement (Sami Tolvanen) - Recursive build CC_FLAGS_LTO fix (Alexander Lobakin)" * tag 'clang-lto-v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: kbuild: prevent CC_FLAGS_LTO self-bloating on recursive rebuilds arm64: allow LTO to be selected arm64: disable recordmcount with DYNAMIC_FTRACE_WITH_REGS arm64: vdso: disable LTO drivers/misc/lkdtm: disable LTO for rodata.o efi/libstub: disable LTO scripts/mod: disable LTO for empty.c modpost: lto: strip .lto from module names PCI: Fix PREL32 relocations for LTO init: lto: fix PREL32 relocations init: lto: ensure initcall ordering kbuild: lto: add a default list of used symbols kbuild: lto: merge module sections kbuild: lto: limit inlining kbuild: lto: fix module versioning kbuild: add support for Clang LTO tracing: move function tracer options to Kconfig
2021-02-23arm64: uprobe: Return EOPNOTSUPP for AARCH32 instruction probingHe Zhe
As stated in linux/errno.h, ENOTSUPP should never be seen by user programs. When we set up uprobe with 32-bit perf and arm64 kernel, we would see the following vague error without useful hint. The sys_perf_event_open() syscall returned with 524 (INTERNAL ERROR: strerror_r(524, [buf], 128)=22) Use EOPNOTSUPP instead to indicate such cases. Signed-off-by: He Zhe <zhe.he@windriver.com> Link: https://lore.kernel.org/r/20210223082535.48730-1-zhe.he@windriver.com Cc: <stable@vger.kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2021-02-21arch: setup PF_IO_WORKER threads like PF_KTHREADJens Axboe
PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the sense that we don't assign ->set_child_tid with our own structure. Just ensure that every arch sets up the PF_IO_WORKER threads like kthreads in the arch implementation of copy_thread(). Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-21Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "x86: - Support for userspace to emulate Xen hypercalls - Raise the maximum number of user memslots - Scalability improvements for the new MMU. Instead of the complex "fast page fault" logic that is used in mmu.c, tdp_mmu.c uses an rwlock so that page faults are concurrent, but the code that can run against page faults is limited. Right now only page faults take the lock for reading; in the future this will be extended to some cases of page table destruction. I hope to switch the default MMU around 5.12-rc3 (some testing was delayed due to Chinese New Year). - Cleanups for MAXPHYADDR checks - Use static calls for vendor-specific callbacks - On AMD, use VMLOAD/VMSAVE to save and restore host state - Stop using deprecated jump label APIs - Workaround for AMD erratum that made nested virtualization unreliable - Support for LBR emulation in the guest - Support for communicating bus lock vmexits to userspace - Add support for SEV attestation command - Miscellaneous cleanups PPC: - Support for second data watchpoint on POWER10 - Remove some complex workarounds for buggy early versions of POWER9 - Guest entry/exit fixes ARM64: - Make the nVHE EL2 object relocatable - Cleanups for concurrent translation faults hitting the same page - Support for the standard TRNG hypervisor call - A bunch of small PMU/Debug fixes - Simplification of the early init hypercall handling Non-KVM changes (with acks): - Detection of contended rwlocks (implemented only for qrwlocks, because KVM only needs it for x86) - Allow __DISABLE_EXPORTS from assembly code - Provide a saner follow_pfn replacements for modules" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (192 commits) KVM: x86/xen: Explicitly pad struct compat_vcpu_info to 64 bytes KVM: selftests: Don't bother mapping GVA for Xen shinfo test KVM: selftests: Fix hex vs. decimal snafu in Xen test KVM: selftests: Fix size of memslots created by Xen tests KVM: selftests: Ignore recently added Xen tests' build output KVM: selftests: Add missing header file needed by xAPIC IPI tests KVM: selftests: Add operand to vmsave/vmload/vmrun in svm.c KVM: SVM: Make symbol 'svm_gp_erratum_intercept' static locking/arch: Move qrwlock.h include after qspinlock.h KVM: PPC: Book3S HV: Fix host radix SLB optimisation with hash guests KVM: PPC: Book3S HV: Ensure radix guest has no SLB entries KVM: PPC: Don't always report hash MMU capability for P9 < DD2.2 KVM: PPC: Book3S HV: Save and restore FSCR in the P9 path KVM: PPC: remove unneeded semicolon KVM: PPC: Book3S HV: Use POWER9 SLBIA IH=6 variant to clear SLB KVM: PPC: Book3S HV: No need to clear radix host SLB before loading HPT guest KVM: PPC: Book3S HV: Fix radix guest SLB side channel KVM: PPC: Book3S HV: Remove support for running HPT guest on RPT host without mixed mode support KVM: PPC: Book3S HV: Introduce new capability for 2nd DAWR KVM: PPC: Book3S HV: Add infrastructure to support 2nd DAWR ...
2021-02-21Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: - vDSO build improvements including support for building with BSD. - Cleanup to the AMU support code and initialisation rework to support cpufreq drivers built as modules. - Removal of synthetic frame record from exception stack when entering the kernel from EL0. - Add support for the TRNG firmware call introduced by Arm spec DEN0098. - Cleanup and refactoring across the board. - Avoid calling arch_get_random_seed_long() from add_interrupt_randomness() - Perf and PMU updates including support for Cortex-A78 and the v8.3 SPE extensions. - Significant steps along the road to leaving the MMU enabled during kexec relocation. - Faultaround changes to initialise prefaulted PTEs as 'old' when hardware access-flag updates are supported, which drastically improves vmscan performance. - CPU errata updates for Cortex-A76 (#1463225) and Cortex-A55 (#1024718) - Preparatory work for yielding the vector unit at a finer granularity in the crypto code, which in turn will one day allow us to defer softirq processing when it is in use. - Support for overriding CPU ID register fields on the command-line. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (85 commits) drivers/perf: Replace spin_lock_irqsave to spin_lock mm: filemap: Fix microblaze build failure with 'mmu_defconfig' arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+ arm64: cpufeatures: Allow disabling of Pointer Auth from the command-line arm64: Defer enabling pointer authentication on boot core arm64: cpufeatures: Allow disabling of BTI from the command-line arm64: Move "nokaslr" over to the early cpufeature infrastructure KVM: arm64: Document HVC_VHE_RESTART stub hypercall arm64: Make kvm-arm.mode={nvhe, protected} an alias of id_aa64mmfr1.vh=0 arm64: Add an aliasing facility for the idreg override arm64: Honor VHE being disabled from the command-line arm64: Allow ID_AA64MMFR1_EL1.VH to be overridden from the command line arm64: cpufeature: Add an early command-line cpufeature override facility arm64: Extract early FDT mapping from kaslr_early_init() arm64: cpufeature: Use IDreg override in __read_sysreg_by_encoding() arm64: cpufeature: Add global feature override facility arm64: Move SCTLR_EL1 initialisation to EL-agnostic code arm64: Simplify init_el2_state to be non-VHE only arm64: Move VHE-specific SPE setup to mutate_to_vhe() arm64: Drop early setting of MDSCR_EL2.TPMS ...
2021-02-19arm64: kexec_file: fix memory leakage in create_dtb() when fdt_open_into() failsqiuguorui1
in function create_dtb(), if fdt_open_into() fails, we need to vfree buf before return. Fixes: 52b2a8af7436 ("arm64: kexec_file: load initrd and device-tree") Cc: stable@vger.kernel.org # v5.0 Signed-off-by: qiuguorui1 <qiuguorui1@huawei.com> Link: https://lore.kernel.org/r/20210218125900.6810-1-qiuguorui1@huawei.com Signed-off-by: Will Deacon <will@kernel.org>
2021-02-19arm64: spectre: Prevent lockdep splat on v4 mitigation enable pathWill Deacon
The Spectre-v4 workaround is re-configured when resuming from suspend, as the firmware may have re-enabled the mitigation despite the user previously asking for it to be disabled. Enabling or disabling the workaround can result in an undefined instruction exception on CPUs which implement PSTATE.SSBS but only allow it to be configured by adjusting the SPSR on exception return. We handle this by installing an 'undef hook' which effectively emulates the access. Installing this hook requires us to take a couple of spinlocks both to avoid corrupting the internal list of hooks but also to ensure that we don't run into an unhandled exception. Unfortunately, when resuming from suspend, we haven't yet called rcu_idle_exit() and so lockdep gets angry about "suspicious RCU usage". In doing so, it tries to print a warning, which leads it to get even more suspicious, this time about itself: | rcu_scheduler_active = 2, debug_locks = 1 | RCU used illegally from extended quiescent state! | 1 lock held by swapper/0: | #0: (logbuf_lock){-.-.}-{2:2}, at: vprintk_emit+0x88/0x198 | | Call trace: | dump_backtrace+0x0/0x1d8 | show_stack+0x18/0x24 | dump_stack+0xe0/0x17c | lockdep_rcu_suspicious+0x11c/0x134 | trace_lock_release+0xa0/0x160 | lock_release+0x3c/0x290 | _raw_spin_unlock+0x44/0x80 | vprintk_emit+0xbc/0x198 | vprintk_default+0x44/0x6c | vprintk_func+0x1f4/0x1fc | printk+0x54/0x7c | lockdep_rcu_suspicious+0x30/0x134 | trace_lock_acquire+0xa0/0x188 | lock_acquire+0x50/0x2fc | _raw_spin_lock+0x68/0x80 | spectre_v4_enable_mitigation+0xa8/0x30c | __cpu_suspend_exit+0xd4/0x1a8 | cpu_suspend+0xa0/0x104 | psci_cpu_suspend_enter+0x3c/0x5c | psci_enter_idle_state+0x44/0x74 | cpuidle_enter_state+0x148/0x2f8 | cpuidle_enter+0x38/0x50 | do_idle+0x1f0/0x2b4 Prevent these splats by running __cpu_suspend_exit() with RCU watching. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Suggested-by: "Paul E . McKenney" <paulmck@kernel.org> Reported-by: Sami Tolvanen <samitolvanen@google.com> Fixes: c28762070ca6 ("arm64: Rewrite Spectre-v4 mitigation code") Cc: <stable@vger.kernel.org> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20210218140346.5224-1-will@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2021-02-12arm64: mte: Allow PTRACE_PEEKMTETAGS access to the zero pageCatalin Marinas
The ptrace(PTRACE_PEEKMTETAGS) implementation checks whether the user page has valid tags (mapped with PROT_MTE) by testing the PG_mte_tagged page flag. If this bit is cleared, ptrace(PTRACE_PEEKMTETAGS) returns -EIO. A newly created (PROT_MTE) mapping points to the zero page which had its tags zeroed during cpu_enable_mte(). If there were no prior writes to this mapping, ptrace(PTRACE_PEEKMTETAGS) fails with -EIO since the zero page does not have the PG_mte_tagged flag set. Set PG_mte_tagged on the zero page when its tags are cleared during boot. In addition, to avoid ptrace(PTRACE_PEEKMTETAGS) succeeding on !PROT_MTE mappings pointing to the zero page, change the __access_remote_tags() check to (vm_flags & VM_MTE) instead of PG_mte_tagged. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Fixes: 34bfeea4a9e9 ("arm64: mte: Clear the tags when a page is mapped in user-space with PROT_MTE") Cc: <stable@vger.kernel.org> # 5.10.x Cc: Will Deacon <will@kernel.org> Reported-by: Luis Machado <luis.machado@linaro.org> Tested-by: Luis Machado <luis.machado@linaro.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20210210180316.23654-1-catalin.marinas@arm.com
2021-02-12Merge branch 'for-next/vdso' into for-next/coreWill Deacon
vDSO build improvements. * for-next/vdso: arm64: Support running gen_vdso_offsets.sh with BSD userland. arm64: do not descend to vdso directories twice
2021-02-12Merge branch 'for-next/topology' into for-next/coreWill Deacon
Cleanup to the AMU support code and initialisation rework to support cpufreq drivers built as modules. * for-next/topology: arm64: topology: Make AMUs work with modular cpufreq drivers arm64: topology: Reorder init_amu_fie() a bit arm64: topology: Avoid the have_policy check
2021-02-12Merge branch 'for-next/stacktrace' into for-next/coreWill Deacon
Remove synthetic frame record from exception stack when entering from userspace. * for-next/stacktrace: arm64: remove EL0 exception frame record
2021-02-12Merge branch 'for-next/perf' into for-next/coreWill Deacon
Perf and PMU updates including support for Cortex-A78 and the v8.3 SPE extensions. * for-next/perf: drivers/perf: Replace spin_lock_irqsave to spin_lock dt-bindings: arm: add Cortex-A78 binding arm64: perf: add support for Cortex-A78 arm64: perf: Constify static attribute_group structs drivers/perf: Prevent forced unbinding of ARM_DMC620_PMU drivers perf/arm-cmn: Move IRQs when migrating context perf/arm-cmn: Fix PMU instance naming perf: Constify static struct attribute_group perf: hisi: Constify static struct attribute_group perf/imx_ddr: Constify static struct attribute_group perf: qcom: Constify static struct attribute_group drivers/perf: Add support for ARMv8.3-SPE
2021-02-12Merge branch 'for-next/misc' into for-next/coreWill Deacon
Miscellaneous arm64 changes for 5.12. * for-next/misc: arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+ arm64: vmlinux.ld.S: add assertion for tramp_pg_dir offset arm64: vmlinux.ld.S: add assertion for reserved_pg_dir offset arm64/ptdump:display the Linear Mapping start marker arm64: ptrace: Fix missing return in hw breakpoint code KVM: arm64: Move __hyp_set_vectors out of .hyp.text arm64: Include linux/io.h in mm/mmap.c arm64: cacheflush: Remove stale comment arm64: mm: Remove unused header file arm64/sparsemem: reduce SECTION_SIZE_BITS arm64/mm: Add warning for outside range requests in vmemmap_populate() arm64: Drop workaround for broken 'S' constraint with GCC 4.9
2021-02-12Merge branch 'for-next/kexec' into for-next/coreWill Deacon
Significant steps along the road to leaving the MMU enabled during kexec relocation. * for-next/kexec: arm64: hibernate: add __force attribute to gfp_t casting arm64: kexec: arm64_relocate_new_kernel don't use x0 as temp arm64: kexec: arm64_relocate_new_kernel clean-ups and optimizations arm64: kexec: call kexec_image_info only once arm64: kexec: move relocation function setup arm64: trans_pgd: hibernate: idmap the single page that holds the copy page routines arm64: mm: Always update TCR_EL1 from __cpu_set_tcr_t0sz() arm64: trans_pgd: pass NULL instead of init_mm to *_populate functions arm64: trans_pgd: pass allocator trans_pgd_create_copy arm64: trans_pgd: make trans_pgd_map_page generic arm64: hibernate: move page handling function to new trans_pgd.c arm64: hibernate: variable pudp is used instead of pd4dp arm64: kexec: make dtb_mem always enabled