Re: [Crash-utility] [PATCH] x86_64: fix "bt" command on 5.12-rc1 and later kernels

Fix "bt" command on Linux 5.12-rc1 and later kernels that contains kernel commit 951c2a51ae75 ("x86/irq/64: Adjust the per CPU irq stack pointer by 8"). Without the patch, the "bt" command and some options that read irq stack fails with the error message "bt: read of stack at <address> failed". Signed-off-by: Kazuhito Hagio <k-hagio-ab(a)nec.com&gt; --- x86_64.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/x86_64.c b/x86_64.c index 23a40a04bbc4..f5b2f7b5f040 100644 --- a/x86_64.c +++ b/x86_64.c @@ -1326,6 +1326,8 @@ x86_64_per_cpu_init(void) KVADDR, &hardirq_stack_ptr, sizeof(void *), "hardirq_stack_ptr (per_cpu)", QUIET|RETURN_ON_ERROR)) continue; + if (hardirq_stack_ptr != PAGEBASE(hardirq_stack_ptr)) + hardirq_stack_ptr += 8; ms->stkinfo.ibase[i] = hardirq_stack_ptr - ms->stkinfo.isize; } else if (irq_sp) ms->stkinfo.ibase[i] = irq_sp->value + kt->__per_cpu_offset[i];