kernel.git/arch/arm64/kernel/probes, branch linux-5.13.y

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2021-04-26T17:25:03Z

Pull arm64 updates from Catalin Marinas: - MTE asynchronous support for KASan. Previously only synchronous (slower) mode was supported. Asynchronous is faster but does not allow precise identification of the illegal access. - Run kernel mode SIMD with softirqs disabled. This allows using NEON in softirq context for crypto performance improvements. The conditional yield support is modified to take softirqs into account and reduce the latency. - Preparatory patches for Apple M1: handle CPUs that only have the VHE mode available (host kernel running at EL2), add FIQ support. - arm64 perf updates: support for HiSilicon PA and SLLC PMU drivers, new functions for the HiSilicon HHA and L3C PMU, cleanups. - Re-introduce support for execute-only user permissions but only when the EPAN (Enhanced Privileged Access Never) architecture feature is available. - Disable fine-grained traps at boot and improve the documented boot requirements. - Support CONFIG_KASAN_VMALLOC on arm64 (only with KASAN_GENERIC). - Add hierarchical eXecute Never permissions for all page tables. - Add arm64 prctl(PR_PAC_{SET,GET}_ENABLED_KEYS) allowing user programs to control which PAC keys are enabled in a particular task. - arm64 kselftests for BTI and some improvements to the MTE tests. - Minor improvements to the compat vdso and sigpage. - Miscellaneous cleanups. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (86 commits) arm64/sve: Add compile time checks for SVE hooks in generic functions arm64/kernel/probes: Use BUG_ON instead of if condition followed by BUG. arm64: pac: Optimize kernel entry/exit key installation code paths arm64: Introduce prctl(PR_PAC_{SET,GET}_ENABLED_KEYS) arm64: mte: make the per-task SCTLR_EL1 field usable elsewhere arm64/sve: Remove redundant system_supports_sve() tests arm64: fpsimd: run kernel mode NEON with softirqs disabled arm64: assembler: introduce wxN aliases for wN registers arm64: assembler: remove conditional NEON yield macros kasan, arm64: tests supports for HW_TAGS async mode arm64: mte: Report async tag faults before suspend arm64: mte: Enable async tag check fault arm64: mte: Conditionally compile mte_enable_kernel_*() arm64: mte: Enable TCO in functions that can read beyond buffer limits kasan: Add report for async mode arm64: mte: Drop arch_enable_tagging() kasan: Add KASAN mode kernel parameter arm64: mte: Add asynchronous mode support arm64: Get rid of CONFIG_ARM64_VHE arm64: Cope with CPUs stuck in VHE mode ...

arm64/kernel/probes: Use BUG_ON instead of if condition followed by BUG.

2021-04-13T16:52:40Z

It can be optimized at compile time. Signed-off-by: zhouchuangao Reviewed-by: Masami Hiramatsu Link: https://lore.kernel.org/r/1617105472-6081-1-git-send-email-zhouchuangao@vivo.com Signed-off-by: Catalin Marinas

arm64: kprobes: Restore local irqflag if kprobes is cancelled

2021-04-13T08:30:16Z

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 Acked-by: Masami Hiramatsu Link: https://lore.kernel.org/r/20210412174101.6bfb0594@xhacker.debian Signed-off-by: Will Deacon

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2021-02-26T18:19:03Z

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

arm64: uprobe: Return EOPNOTSUPP for AARCH32 instruction probing

2021-02-23T10:38:27Z

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 Link: https://lore.kernel.org/r/20210223082535.48730-1-zhe.he@windriver.com Cc: Signed-off-by: Will Deacon

arm64: kprobes: Fix Uexpected kernel BRK exception at EL1

2021-01-22T16:05:29Z

I was hitting the below panic continuously when attaching kprobes to scheduler functions [ 159.045212] Unexpected kernel BRK exception at EL1 [ 159.053753] Internal error: BRK handler: f2000006 [#1] PREEMPT SMP [ 159.059954] Modules linked in: [ 159.063025] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.11.0-rc4-00008-g1e2a199f6ccd #56 [rt-app] [1] Exiting.[ 159.071166] Hardware name: ARM Juno development board (r2) (DT) [ 159.079689] pstate: 600003c5 (nZCv DAIF -PAN -UAO -TCO BTYPE=--) [ 159.085723] pc : 0xffff80001624501c [ 159.089377] lr : attach_entity_load_avg+0x2ac/0x350 [ 159.094271] sp : ffff80001622b640 [rt-app] [0] Exiting.[ 159.097591] x29: ffff80001622b640 x28: 0000000000000001 [ 159.105515] x27: 0000000000000049 x26: ffff000800b79980 [ 159.110847] x25: ffff00097ef37840 x24: 0000000000000000 [ 159.116331] x23: 00000024eacec1ec x22: ffff00097ef12b90 [ 159.121663] x21: ffff00097ef37700 x20: ffff800010119170 [rt-app] [11] Exiting.[ 159.126995] x19: ffff00097ef37840 x18: 000000000000000e [ 159.135003] x17: 0000000000000001 x16: 0000000000000019 [ 159.140335] x15: 0000000000000000 x14: 0000000000000000 [ 159.145666] x13: 0000000000000002 x12: 0000000000000002 [ 159.150996] x11: ffff80001592f9f0 x10: 0000000000000060 [ 159.156327] x9 : ffff8000100f6f9c x8 : be618290de0999a1 [ 159.161659] x7 : ffff80096a4b1000 x6 : 0000000000000000 [ 159.166990] x5 : ffff00097ef37840 x4 : 0000000000000000 [ 159.172321] x3 : ffff000800328948 x2 : 0000000000000000 [ 159.177652] x1 : 0000002507d52fec x0 : ffff00097ef12b90 [ 159.182983] Call trace: [ 159.185433] 0xffff80001624501c [ 159.188581] update_load_avg+0x2d0/0x778 [ 159.192516] enqueue_task_fair+0x134/0xe20 [ 159.196625] enqueue_task+0x4c/0x2c8 [ 159.200211] ttwu_do_activate+0x70/0x138 [ 159.204147] sched_ttwu_pending+0xbc/0x160 [ 159.208253] flush_smp_call_function_queue+0x16c/0x320 [ 159.213408] generic_smp_call_function_single_interrupt+0x1c/0x28 [ 159.219521] ipi_handler+0x1e8/0x3c8 [ 159.223106] handle_percpu_devid_irq+0xd8/0x460 [ 159.227650] generic_handle_irq+0x38/0x50 [ 159.231672] __handle_domain_irq+0x6c/0xc8 [ 159.235781] gic_handle_irq+0xcc/0xf0 [ 159.239452] el1_irq+0xb4/0x180 [ 159.242600] rcu_is_watching+0x28/0x70 [ 159.246359] rcu_read_lock_held_common+0x44/0x88 [ 159.250991] rcu_read_lock_any_held+0x30/0xc0 [ 159.255360] kretprobe_dispatcher+0xc4/0xf0 [ 159.259555] __kretprobe_trampoline_handler+0xc0/0x150 [ 159.264710] trampoline_probe_handler+0x38/0x58 [ 159.269255] kretprobe_trampoline+0x70/0xc4 [ 159.273450] run_rebalance_domains+0x54/0x80 [ 159.277734] __do_softirq+0x164/0x684 [ 159.281406] irq_exit+0x198/0x1b8 [ 159.284731] __handle_domain_irq+0x70/0xc8 [ 159.288840] gic_handle_irq+0xb0/0xf0 [ 159.292510] el1_irq+0xb4/0x180 [ 159.295658] arch_cpu_idle+0x18/0x28 [ 159.299245] default_idle_call+0x9c/0x3e8 [ 159.303265] do_idle+0x25c/0x2a8 [ 159.306502] cpu_startup_entry+0x2c/0x78 [ 159.310436] secondary_start_kernel+0x160/0x198 [ 159.314984] Code: d42000c0 aa1e03e9 d42000c0 aa1e03e9 (d42000c0) After a bit of head scratching and debugging it turned out that it is due to kprobe handler being interrupted by a tick that causes us to go into (I think another) kprobe handler. The culprit was kprobe_breakpoint_ss_handler() returning DBG_HOOK_ERROR which leads to the Unexpected kernel BRK exception. Reverting commit ba090f9cafd5 ("arm64: kprobes: Remove redundant kprobe_step_ctx") seemed to fix the problem for me. Further analysis showed that kcb->kprobe_status is set to KPROBE_REENTER when the error occurs. By teaching kprobe_breakpoint_ss_handler() to handle this status I can no longer reproduce the problem. Fixes: ba090f9cafd5 ("arm64: kprobes: Remove redundant kprobe_step_ctx") Signed-off-by: Qais Yousef Acked-by: Will Deacon Acked-by: Masami Hiramatsu Link: https://lore.kernel.org/r/20210122110909.3324607-1-qais.yousef@arm.com Signed-off-by: Catalin Marinas

arm64: rename S_FRAME_SIZE to PT_REGS_SIZE

2021-01-13T15:09:06Z

S_FRAME_SIZE is the size of the pt_regs structure, no longer the size of the kernel stack frame, the name is misleading. In keeping with arm32, rename S_FRAME_SIZE to PT_REGS_SIZE. Signed-off-by: Jianlin Lv Acked-by: Mark Rutland Link: https://lore.kernel.org/r/20210112015813.2340969-1-Jianlin.Lv@arm.com Signed-off-by: Catalin Marinas

arm64: kprobes: Remove redundant kprobe_step_ctx

2020-11-10T17:12:30Z

The kprobe_step_ctx (kcb->ss_ctx) has ss_pending and match_addr, but those are redundant because those can be replaced by KPROBE_HIT_SS and &cur_kprobe->ainsn.api.insn[1] respectively. To simplify the code, remove the kprobe_step_ctx. Signed-off-by: Masami Hiramatsu Reviewed-by: Jean-Philippe Brucker Acked-by: Will Deacon Link: https://lore.kernel.org/r/20201103134900.337243-2-jean-philippe@linaro.org Signed-off-by: Catalin Marinas

arm64: kprobes: Use BRK instead of single-step when executing instructions out-of-line

2020-11-03T14:03:38Z

Commit 36dadef23fcc ("kprobes: Init kprobes in early_initcall") enabled using kprobes from early_initcall. Unfortunately at this point the hardware debug infrastructure is not operational. The OS lock may still be locked, and the hardware watchpoints may have unknown values when kprobe enables debug monitors to single-step instructions. Rather than using hardware single-step, append a BRK instruction after the instruction to be executed out-of-line. Fixes: 36dadef23fcc ("kprobes: Init kprobes in early_initcall") Suggested-by: Will Deacon Signed-off-by: Jean-Philippe Brucker Acked-by: Masami Hiramatsu Link: https://lore.kernel.org/r/20201103134900.337243-1-jean-philippe@linaro.org Signed-off-by: Will Deacon

Merge tag 'perf-kprobes-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-10-12T21:21:15Z

Pull perf/kprobes updates from Ingo Molnar: "This prepares to unify the kretprobe trampoline handler and make kretprobe lockless (those patches are still work in progress)" * tag 'perf-kprobes-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes: Fix to check probe enabled before disarm_kprobe_ftrace() kprobes: Make local functions static kprobes: Free kretprobe_instance with RCU callback kprobes: Remove NMI context check sparc: kprobes: Use generic kretprobe trampoline handler sh: kprobes: Use generic kretprobe trampoline handler s390: kprobes: Use generic kretprobe trampoline handler powerpc: kprobes: Use generic kretprobe trampoline handler parisc: kprobes: Use generic kretprobe trampoline handler mips: kprobes: Use generic kretprobe trampoline handler ia64: kprobes: Use generic kretprobe trampoline handler csky: kprobes: Use generic kretprobe trampoline handler arc: kprobes: Use generic kretprobe trampoline handler arm64: kprobes: Use generic kretprobe trampoline handler arm: kprobes: Use generic kretprobe trampoline handler x86/kprobes: Use generic kretprobe trampoline handler kprobes: Add generic kretprobe trampoline handler