Messages in this thread | | | From | Pingfan Liu <> | Date | Thu, 26 Nov 2020 16:05:31 +0800 | Subject | Re: [PATCH 2/2] x86/machine_kexec: disable PMU before jumping to new kernel |
| |
Sorry that I had made a misunderstanding of the code.
Nacked it
On Mon, Nov 23, 2020 at 1:37 PM Pingfan Liu <kernelfans@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 <kernelfans@gmail.com> > Cc: Peter Zijlstra <peterz@infradead.org> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: Arnaldo Carvalho de Melo <acme@kernel.org> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> > Cc: Jiri Olsa <jolsa@redhat.com> > Cc: Namhyung Kim <namhyung@kernel.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Borislav Petkov <bp@alien8.de> > Cc: "H. Peter Anvin" <hpa@zytor.com> > Cc: Omar Sandoval <osandov@fb.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Mike Rapoport <rppt@kernel.org> > To: x86@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 >
| |