Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch kvm-arm64/dump-instr into kvmarm-master/next
* kvm-arm64/dump-instr:
: .
: Dump the isntruction stream on panic, just like the rest of the kernel
: already does.
:
: Patches courtesy of Mostafa Saleh (20250909133631.3844423-1-smostafa@google.com)
: .
KVM: arm64: Map hyp text as RO and dump instr on panic
KVM: arm64: Dump instruction on hyp panic
Signed-off-by: Marc Zyngier <maz@kernel.org>
+23
-8
+1
arch/arm64/include/asm/traps.h
+1
arch/arm64/include/asm/traps.h
···
36
36
int ubsan_brk_handler(struct pt_regs *regs, unsigned long esr);
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int early_brk64(unsigned long addr, unsigned long esr, struct pt_regs *regs);
39
+
void dump_kernel_instr(unsigned long kaddr);
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/*
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* Move regs->pc to next instruction and do necessary setup before it
+9
-6
arch/arm64/kernel/traps.c
+9
-6
arch/arm64/kernel/traps.c
···
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int show_unhandled_signals = 0;
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-
static void dump_kernel_instr(const char *lvl, struct pt_regs *regs)
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+
void dump_kernel_instr(unsigned long kaddr)
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{
154
-
unsigned long addr = instruction_pointer(regs);
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char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
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int i;
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-
if (user_mode(regs))
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+
if (!is_ttbr1_addr(kaddr))
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return;
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for (i = -4; i < 1; i++) {
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unsigned int val, bad;
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-
bad = aarch64_insn_read(&((u32 *)addr)[i], &val);
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+
bad = aarch64_insn_read(&((u32 *)kaddr)[i], &val);
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if (!bad)
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p += sprintf(p, i == 0 ? "(%08x) " : "%08x ", val);
···
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p += sprintf(p, i == 0 ? "(????????) " : "???????? ");
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}
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-
printk("%sCode: %s\n", lvl, str);
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+
printk(KERN_EMERG "Code: %s\n", str);
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}
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#define S_SMP " SMP"
···
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{
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static int die_counter;
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int ret;
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+
unsigned long addr = instruction_pointer(regs);
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pr_emerg("Internal error: %s: %016lx [#%d] " S_SMP "\n",
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str, err, ++die_counter);
···
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print_modules();
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show_regs(regs);
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-
dump_kernel_instr(KERN_EMERG, regs);
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+
if (user_mode(regs))
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+
return ret;
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+
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+
dump_kernel_instr(addr);
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return ret;
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}
+3
arch/arm64/kvm/handle_exit.c
+3
arch/arm64/kvm/handle_exit.c
···
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/* Dump the nVHE hypervisor backtrace */
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kvm_nvhe_dump_backtrace(hyp_offset);
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+
/* Dump the faulting instruction */
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+
dump_kernel_instr(panic_addr + kaslr_offset());
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+
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/*
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* Hyp has panicked and we're going to handle that by panicking the
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* kernel. The kernel offset will be revealed in the panic so we're
+10
-2
arch/arm64/kvm/hyp/nvhe/setup.c
+10
-2
arch/arm64/kvm/hyp/nvhe/setup.c
···
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enum pkvm_page_state state;
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struct hyp_page *page;
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phys_addr_t phys;
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+
enum kvm_pgtable_prot prot;
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if (!kvm_pte_valid(ctx->old))
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return 0;
···
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* configured in the hypervisor stage-1, and make sure to propagate them
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* to the hyp_vmemmap state.
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*/
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-
state = pkvm_getstate(kvm_pgtable_hyp_pte_prot(ctx->old));
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+
prot = kvm_pgtable_hyp_pte_prot(ctx->old);
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+
state = pkvm_getstate(prot);
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switch (state) {
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case PKVM_PAGE_OWNED:
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set_hyp_state(page, PKVM_PAGE_OWNED);
218
-
return host_stage2_set_owner_locked(phys, PAGE_SIZE, PKVM_ID_HYP);
218
+
/* hyp text is RO in the host stage-2 to be inspected on panic. */
219
+
if (prot == PAGE_HYP_EXEC) {
220
+
set_host_state(page, PKVM_NOPAGE);
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+
return host_stage2_idmap_locked(phys, PAGE_SIZE, KVM_PGTABLE_PROT_R);
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+
} else {
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+
return host_stage2_set_owner_locked(phys, PAGE_SIZE, PKVM_ID_HYP);
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+
}
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case PKVM_PAGE_SHARED_OWNED:
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set_hyp_state(page, PKVM_PAGE_SHARED_OWNED);
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set_host_state(page, PKVM_PAGE_SHARED_BORROWED);