Sorry that I had made a misunderstanding of the code.
Nacked it
On Mon, Nov 23, 2020 at 1:37 PM Pingfan Liu <kernelf...@gmail.com> wrote:
>
> During jumping to the new kernel, on the crashed cpu, the memory mapping
> switches from an old one to an identity one. It had better disable PMU to
> suppress NMI, which can be delivered using the old mapping.
>
> Also on x86_64, idt_invalidate() to clear idt as on 32 bits.
>
> Signed-off-by: Pingfan Liu <kernelf...@gmail.com>
> Cc: Peter Zijlstra <pet...@infradead.org>
> Cc: Ingo Molnar <mi...@redhat.com>
> Cc: Arnaldo Carvalho de Melo <a...@kernel.org>
> Cc: Mark Rutland <mark.rutl...@arm.com>
> Cc: Alexander Shishkin <alexander.shish...@linux.intel.com>
> Cc: Jiri Olsa <jo...@redhat.com>
> Cc: Namhyung Kim <namhy...@kernel.org>
> Cc: Thomas Gleixner <t...@linutronix.de>
> Cc: Borislav Petkov <b...@alien8.de>
> Cc: "H. Peter Anvin" <h...@zytor.com>
> Cc: Omar Sandoval <osan...@fb.com>
> Cc: Andrew Morton <a...@linux-foundation.org>
> Cc: Mike Rapoport <r...@kernel.org>
> To: x...@kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
> arch/x86/kernel/machine_kexec_32.c | 1 +
> arch/x86/kernel/machine_kexec_64.c | 3 +++
> 2 files changed, 4 insertions(+)
>
> diff --git a/arch/x86/kernel/machine_kexec_32.c
> b/arch/x86/kernel/machine_kexec_32.c
> index 64b00b0..72c6100 100644
> --- a/arch/x86/kernel/machine_kexec_32.c
> +++ b/arch/x86/kernel/machine_kexec_32.c
> @@ -191,6 +191,7 @@ void machine_kexec(struct kimage *image)
> /* Interrupts aren't acceptable while we reboot */
> local_irq_disable();
> hw_breakpoint_disable();
> + perf_pmu_disable_all();
>
> if (image->preserve_context) {
> #ifdef CONFIG_X86_IO_APIC
> diff --git a/arch/x86/kernel/machine_kexec_64.c
> b/arch/x86/kernel/machine_kexec_64.c
> index a29a44a..238893e 100644
> --- a/arch/x86/kernel/machine_kexec_64.c
> +++ b/arch/x86/kernel/machine_kexec_64.c
> @@ -17,6 +17,7 @@
> #include <linux/suspend.h>
> #include <linux/vmalloc.h>
> #include <linux/efi.h>
> +#include <linux/perf_event.h>
>
> #include <asm/init.h>
> #include <asm/tlbflush.h>
> @@ -338,6 +339,8 @@ void machine_kexec(struct kimage *image)
> /* Interrupts aren't acceptable while we reboot */
> local_irq_disable();
> hw_breakpoint_disable();
> + perf_pmu_disable_all();
> + idt_invalidate(phys_to_virt(0));
>
> if (image->preserve_context) {
> #ifdef CONFIG_X86_IO_APIC
> --
> 2.7.5
>
