diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2024-06-14 12:59:01 +0300 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2024-06-17 17:46:20 +0200 |
| commit | 26ba7353caaa7140561d3f7693a77a3eb68c722c (patch) | |
| tree | 4c1305cbc1c7cbd0b7c581b5dae033dadb51363f | |
| parent | db0936830a2fcc35e2b283275acf61b6d3ae1e11 (diff) | |
x86/smp: Add smp_ops.stop_this_cpu() callback
If the helper is defined, it is called instead of halt() to stop the CPU at the
end of stop_this_cpu() and on crash CPU shutdown.
ACPI MADT will use it to hand over the CPU to BIOS in order to be able to wake
it up again after kexec.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kai Huang <kai.huang@intel.com>
Tested-by: Tao Liu <ltao@redhat.com>
Link: https://lore.kernel.org/r/20240614095904.1345461-17-kirill.shutemov@linux.intel.com
| -rw-r--r-- | arch/x86/include/asm/smp.h | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/process.c | 7 | ||||
| -rw-r--r-- | arch/x86/kernel/reboot.c | 6 |
3 files changed, 14 insertions, 0 deletions
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index a35936b512fe..ca073f40698f 100644 --- a/arch/x86/include/asm/smp.h +++ b/arch/x86/include/asm/smp.h @@ -35,6 +35,7 @@ struct smp_ops { int (*cpu_disable)(void); void (*cpu_die)(unsigned int cpu); void (*play_dead)(void); + void (*stop_this_cpu)(void); void (*send_call_func_ipi)(const struct cpumask *mask); void (*send_call_func_single_ipi)(int cpu); diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index b8441147eb5e..f63f8fd00a91 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -835,6 +835,13 @@ void __noreturn stop_this_cpu(void *dummy) */ cpumask_clear_cpu(cpu, &cpus_stop_mask); +#ifdef CONFIG_SMP + if (smp_ops.stop_this_cpu) { + smp_ops.stop_this_cpu(); + unreachable(); + } +#endif + for (;;) { /* * Use native_halt() so that memory contents don't change diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index bb7a44af7efd..0e0a4cf6b5eb 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -880,6 +880,12 @@ static int crash_nmi_callback(unsigned int val, struct pt_regs *regs) cpu_emergency_disable_virtualization(); atomic_dec(&waiting_for_crash_ipi); + + if (smp_ops.stop_this_cpu) { + smp_ops.stop_this_cpu(); + unreachable(); + } + /* Assume hlt works */ halt(); for (;;) |