diff options
| author | Zhang Yanfei <zhangyanfei@cn.fujitsu.com> | 2012-12-06 19:40:47 +0400 |
|---|---|---|
| committer | Gleb Natapov <gleb@redhat.com> | 2012-12-06 20:25:36 +0400 |
| commit | f23d1f4a116038c68df224deae6718fde87d8f0d (patch) | |
| tree | 72d414b6fddf5b726559fba66d2f1d7ffc21de7b /arch/x86/kernel/crash.c | |
| parent | c21934632549910188fb5cf40e79033f27a0741b (diff) | |
| download | linux-f23d1f4a116038c68df224deae6718fde87d8f0d.tar.xz | |
x86/kexec: VMCLEAR VMCSs loaded on all cpus if necessary
This patch provides a way to VMCLEAR VMCSs related to guests
on all cpus before executing the VMXOFF when doing kdump. This
is used to ensure the VMCSs in the vmcore updated and
non-corrupted.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Diffstat (limited to 'arch/x86/kernel/crash.c')
| -rw-r--r-- | arch/x86/kernel/crash.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index 13ad89971d47..2f6b8e838d18 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -16,6 +16,7 @@ #include <linux/delay.h> #include <linux/elf.h> #include <linux/elfcore.h> +#include <linux/module.h> #include <asm/processor.h> #include <asm/hardirq.h> @@ -30,6 +31,27 @@ int in_crash_kexec; +/* + * This is used to VMCLEAR all VMCSs loaded on the + * processor. And when loading kvm_intel module, the + * callback function pointer will be assigned. + * + * protected by rcu. + */ +void (*crash_vmclear_loaded_vmcss)(void) = NULL; +EXPORT_SYMBOL_GPL(crash_vmclear_loaded_vmcss); + +static inline void cpu_crash_vmclear_loaded_vmcss(void) +{ + void (*do_vmclear_operation)(void) = NULL; + + rcu_read_lock(); + do_vmclear_operation = rcu_dereference(crash_vmclear_loaded_vmcss); + if (do_vmclear_operation) + do_vmclear_operation(); + rcu_read_unlock(); +} + #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) static void kdump_nmi_callback(int cpu, struct pt_regs *regs) @@ -46,6 +68,11 @@ static void kdump_nmi_callback(int cpu, struct pt_regs *regs) #endif crash_save_cpu(regs, cpu); + /* + * VMCLEAR VMCSs loaded on all cpus if needed. + */ + cpu_crash_vmclear_loaded_vmcss(); + /* Disable VMX or SVM if needed. * * We need to disable virtualization on all CPUs. @@ -88,6 +115,11 @@ void native_machine_crash_shutdown(struct pt_regs *regs) kdump_nmi_shootdown_cpus(); + /* + * VMCLEAR VMCSs loaded on this cpu if needed. + */ + cpu_crash_vmclear_loaded_vmcss(); + /* Booting kdump kernel with VMX or SVM enabled won't work, * because (among other limitations) we can't disable paging * with the virt flags. |