lkml.org 
[lkml]   [2022]   [Jul]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    Subject[PATCH v4 16/18] KVM: arm64: Introduce pkvm_dump_backtrace()
    From
    Dumps the pKVM hypervisor backtrace from EL1 by reading the unwinded
    addresses from the shared stacktrace buffer.

    Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
    ---
    arch/arm64/include/asm/stacktrace/nvhe.h | 49 ++++++++++++++++++++++++
    1 file changed, 49 insertions(+)

    diff --git a/arch/arm64/include/asm/stacktrace/nvhe.h b/arch/arm64/include/asm/stacktrace/nvhe.h
    index c3f94b10f8f0..ec1a4ee21c21 100644
    --- a/arch/arm64/include/asm/stacktrace/nvhe.h
    +++ b/arch/arm64/include/asm/stacktrace/nvhe.h
    @@ -190,5 +190,54 @@ static int notrace unwind_next(struct unwind_state *state)
    }
    NOKPROBE_SYMBOL(unwind_next);

    +#ifdef CONFIG_PROTECTED_NVHE_STACKTRACE
    +DECLARE_KVM_NVHE_PER_CPU(unsigned long [NVHE_STACKTRACE_SIZE/sizeof(long)], pkvm_stacktrace);
    +
    +/**
    + * pkvm_dump_backtrace - Dump the protected nVHE HYP backtrace.
    + *
    + * @hyp_offset: hypervisor offset, used for address translation.
    + *
    + * Dumping of the pKVM HYP backtrace is done by reading the
    + * stack addresses from the shared stacktrace buffer, since the
    + * host cannot direclty access hyperviosr memory in protected
    + * mode.
    + */
    +static inline void pkvm_dump_backtrace(unsigned long hyp_offset)
    +{
    + unsigned long *stacktrace_pos;
    + unsigned long va_mask, pc;
    +
    + stacktrace_pos = (unsigned long *)this_cpu_ptr_nvhe_sym(pkvm_stacktrace);
    + va_mask = GENMASK_ULL(vabits_actual - 1, 0);
    +
    + kvm_err("Protected nVHE HYP call trace:\n");
    +
    + /* The stack trace is terminated by a null entry */
    + for (; *stacktrace_pos; stacktrace_pos++) {
    + /* Mask tags and convert to kern addr */
    + pc = (*stacktrace_pos & va_mask) + hyp_offset;
    + kvm_err(" [<%016lx>] %pB\n", pc, (void *)pc);
    + }
    +
    + kvm_err("---- End of Protected nVHE HYP call trace ----\n");
    +}
    +#else /* !CONFIG_PROTECTED_NVHE_STACKTRACE */
    +static inline void pkvm_dump_backtrace(unsigned long hyp_offset)
    +{
    + kvm_err("Cannot dump pKVM nVHE stacktrace: !CONFIG_PROTECTED_NVHE_STACKTRACE\n");
    +}
    +#endif /* CONFIG_PROTECTED_NVHE_STACKTRACE */
    +
    +/**
    + * kvm_nvhe_dump_backtrace - Dump KVM nVHE hypervisor backtrace.
    + *
    + * @hyp_offset: hypervisor offset, used for address translation.
    + */
    +static inline void kvm_nvhe_dump_backtrace(unsigned long hyp_offset)
    +{
    + if (is_protected_kvm_enabled())
    + pkvm_dump_backtrace(hyp_offset);
    +}
    #endif /* __KVM_NVHE_HYPERVISOR__ */
    #endif /* __ASM_STACKTRACE_NVHE_H */
    --
    2.37.0.170.g444d1eabd0-goog
    \
     
     \ /
      Last update: 2022-07-15 08:15    [W:2.168 / U:0.032 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site