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author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-05 00:59:54 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-05 00:59:54 +0300 |
commit | 7c5c3a6177fa9646884114fc7f2e970b0bc50dc9 (patch) | |
tree | 956857522574ae7cb07d2227dc16e53d7e9e00e7 /arch/arm64/include/asm/stacktrace/common.h | |
parent | f0a892f599c46af673e47418c47c15e69a7b67f4 (diff) | |
parent | 281106f938d3daaea6f8b6723a8217a2a1ef6936 (diff) | |
download | linux-7c5c3a6177fa9646884114fc7f2e970b0bc50dc9.tar.xz |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"Quite a large pull request due to a selftest API overhaul and some
patches that had come in too late for 5.19.
ARM:
- Unwinder implementations for both nVHE modes (classic and
protected), complete with an overflow stack
- Rework of the sysreg access from userspace, with a complete rewrite
of the vgic-v3 view to allign with the rest of the infrastructure
- Disagregation of the vcpu flags in separate sets to better track
their use model.
- A fix for the GICv2-on-v3 selftest
- A small set of cosmetic fixes
RISC-V:
- Track ISA extensions used by Guest using bitmap
- Added system instruction emulation framework
- Added CSR emulation framework
- Added gfp_custom flag in struct kvm_mmu_memory_cache
- Added G-stage ioremap() and iounmap() functions
- Added support for Svpbmt inside Guest
s390:
- add an interface to provide a hypervisor dump for secure guests
- improve selftests to use TAP interface
- enable interpretive execution of zPCI instructions (for PCI
passthrough)
- First part of deferred teardown
- CPU Topology
- PV attestation
- Minor fixes
x86:
- Permit guests to ignore single-bit ECC errors
- Intel IPI virtualization
- Allow getting/setting pending triple fault with
KVM_GET/SET_VCPU_EVENTS
- PEBS virtualization
- Simplify PMU emulation by just using PERF_TYPE_RAW events
- More accurate event reinjection on SVM (avoid retrying
instructions)
- Allow getting/setting the state of the speaker port data bit
- Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls
are inconsistent
- "Notify" VM exit (detect microarchitectural hangs) for Intel
- Use try_cmpxchg64 instead of cmpxchg64
- Ignore benign host accesses to PMU MSRs when PMU is disabled
- Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior
- Allow NX huge page mitigation to be disabled on a per-vm basis
- Port eager page splitting to shadow MMU as well
- Enable CMCI capability by default and handle injected UCNA errors
- Expose pid of vcpu threads in debugfs
- x2AVIC support for AMD
- cleanup PIO emulation
- Fixes for LLDT/LTR emulation
- Don't require refcounted "struct page" to create huge SPTEs
- Miscellaneous cleanups:
- MCE MSR emulation
- Use separate namespaces for guest PTEs and shadow PTEs bitmasks
- PIO emulation
- Reorganize rmap API, mostly around rmap destruction
- Do not workaround very old KVM bugs for L0 that runs with nesting enabled
- new selftests API for CPUID
Generic:
- Fix races in gfn->pfn cache refresh; do not pin pages tracked by
the cache
- new selftests API using struct kvm_vcpu instead of a (vm, id)
tuple"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (606 commits)
selftests: kvm: set rax before vmcall
selftests: KVM: Add exponent check for boolean stats
selftests: KVM: Provide descriptive assertions in kvm_binary_stats_test
selftests: KVM: Check stat name before other fields
KVM: x86/mmu: remove unused variable
RISC-V: KVM: Add support for Svpbmt inside Guest/VM
RISC-V: KVM: Use PAGE_KERNEL_IO in kvm_riscv_gstage_ioremap()
RISC-V: KVM: Add G-stage ioremap() and iounmap() functions
KVM: Add gfp_custom flag in struct kvm_mmu_memory_cache
RISC-V: KVM: Add extensible CSR emulation framework
RISC-V: KVM: Add extensible system instruction emulation framework
RISC-V: KVM: Factor-out instruction emulation into separate sources
RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run
RISC-V: KVM: Make kvm_riscv_guest_timer_init a void function
RISC-V: KVM: Fix variable spelling mistake
RISC-V: KVM: Improve ISA extension by using a bitmap
KVM, x86/mmu: Fix the comment around kvm_tdp_mmu_zap_leafs()
KVM: SVM: Dump Virtual Machine Save Area (VMSA) to klog
KVM: x86/mmu: Treat NX as a valid SPTE bit for NPT
KVM: x86: Do not block APIC write for non ICR registers
...
Diffstat (limited to 'arch/arm64/include/asm/stacktrace/common.h')
-rw-r--r-- | arch/arm64/include/asm/stacktrace/common.h | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/stacktrace/common.h b/arch/arm64/include/asm/stacktrace/common.h new file mode 100644 index 000000000000..f58eb944c46f --- /dev/null +++ b/arch/arm64/include/asm/stacktrace/common.h @@ -0,0 +1,199 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Common arm64 stack unwinder code. + * + * To implement a new arm64 stack unwinder: + * 1) Include this header + * + * 2) Call into unwind_next_common() from your top level unwind + * function, passing it the validation and translation callbacks + * (though the later can be NULL if no translation is required). + * + * See: arch/arm64/kernel/stacktrace.c for the reference implementation. + * + * Copyright (C) 2012 ARM Ltd. + */ +#ifndef __ASM_STACKTRACE_COMMON_H +#define __ASM_STACKTRACE_COMMON_H + +#include <linux/bitmap.h> +#include <linux/bitops.h> +#include <linux/kprobes.h> +#include <linux/types.h> + +enum stack_type { + STACK_TYPE_UNKNOWN, + STACK_TYPE_TASK, + STACK_TYPE_IRQ, + STACK_TYPE_OVERFLOW, + STACK_TYPE_SDEI_NORMAL, + STACK_TYPE_SDEI_CRITICAL, + STACK_TYPE_HYP, + __NR_STACK_TYPES +}; + +struct stack_info { + unsigned long low; + unsigned long high; + enum stack_type type; +}; + +/* + * A snapshot of a frame record or fp/lr register values, along with some + * accounting information necessary for robust unwinding. + * + * @fp: The fp value in the frame record (or the real fp) + * @pc: The lr value in the frame record (or the real lr) + * + * @stacks_done: Stacks which have been entirely unwound, for which it is no + * longer valid to unwind to. + * + * @prev_fp: The fp that pointed to this frame record, or a synthetic value + * of 0. This is used to ensure that within a stack, each + * subsequent frame record is at an increasing address. + * @prev_type: The type of stack this frame record was on, or a synthetic + * value of STACK_TYPE_UNKNOWN. This is used to detect a + * transition from one stack to another. + * + * @kr_cur: When KRETPROBES is selected, holds the kretprobe instance + * associated with the most recently encountered replacement lr + * value. + * + * @task: The task being unwound. + */ +struct unwind_state { + unsigned long fp; + unsigned long pc; + DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); + unsigned long prev_fp; + enum stack_type prev_type; +#ifdef CONFIG_KRETPROBES + struct llist_node *kr_cur; +#endif + struct task_struct *task; +}; + +static inline bool on_stack(unsigned long sp, unsigned long size, + unsigned long low, unsigned long high, + enum stack_type type, struct stack_info *info) +{ + if (!low) + return false; + + if (sp < low || sp + size < sp || sp + size > high) + return false; + + if (info) { + info->low = low; + info->high = high; + info->type = type; + } + return true; +} + +static inline void unwind_init_common(struct unwind_state *state, + struct task_struct *task) +{ + state->task = task; +#ifdef CONFIG_KRETPROBES + state->kr_cur = NULL; +#endif + + /* + * Prime the first unwind. + * + * In unwind_next() we'll check that the FP points to a valid stack, + * which can't be STACK_TYPE_UNKNOWN, and the first unwind will be + * treated as a transition to whichever stack that happens to be. The + * prev_fp value won't be used, but we set it to 0 such that it is + * definitely not an accessible stack address. + */ + bitmap_zero(state->stacks_done, __NR_STACK_TYPES); + state->prev_fp = 0; + state->prev_type = STACK_TYPE_UNKNOWN; +} + +/* + * stack_trace_translate_fp_fn() - Translates a non-kernel frame pointer to + * a kernel address. + * + * @fp: the frame pointer to be updated to its kernel address. + * @type: the stack type associated with frame pointer @fp + * + * Returns true and success and @fp is updated to the corresponding + * kernel virtual address; otherwise returns false. + */ +typedef bool (*stack_trace_translate_fp_fn)(unsigned long *fp, + enum stack_type type); + +/* + * on_accessible_stack_fn() - Check whether a stack range is on any + * of the possible stacks. + * + * @tsk: task whose stack is being unwound + * @sp: stack address being checked + * @size: size of the stack range being checked + * @info: stack unwinding context + */ +typedef bool (*on_accessible_stack_fn)(const struct task_struct *tsk, + unsigned long sp, unsigned long size, + struct stack_info *info); + +static inline int unwind_next_common(struct unwind_state *state, + struct stack_info *info, + on_accessible_stack_fn accessible, + stack_trace_translate_fp_fn translate_fp) +{ + unsigned long fp = state->fp, kern_fp = fp; + struct task_struct *tsk = state->task; + + if (fp & 0x7) + return -EINVAL; + + if (!accessible(tsk, fp, 16, info)) + return -EINVAL; + + if (test_bit(info->type, state->stacks_done)) + return -EINVAL; + + /* + * If fp is not from the current address space perform the necessary + * translation before dereferencing it to get the next fp. + */ + if (translate_fp && !translate_fp(&kern_fp, info->type)) + return -EINVAL; + + /* + * As stacks grow downward, any valid record on the same stack must be + * at a strictly higher address than the prior record. + * + * Stacks can nest in several valid orders, e.g. + * + * TASK -> IRQ -> OVERFLOW -> SDEI_NORMAL + * TASK -> SDEI_NORMAL -> SDEI_CRITICAL -> OVERFLOW + * HYP -> OVERFLOW + * + * ... but the nesting itself is strict. Once we transition from one + * stack to another, it's never valid to unwind back to that first + * stack. + */ + if (info->type == state->prev_type) { + if (fp <= state->prev_fp) + return -EINVAL; + } else { + __set_bit(state->prev_type, state->stacks_done); + } + + /* + * Record this frame record's values and location. The prev_fp and + * prev_type are only meaningful to the next unwind_next() invocation. + */ + state->fp = READ_ONCE(*(unsigned long *)(kern_fp)); + state->pc = READ_ONCE(*(unsigned long *)(kern_fp + 8)); + state->prev_fp = fp; + state->prev_type = info->type; + + return 0; +} + +#endif /* __ASM_STACKTRACE_COMMON_H */ |