diff options
| author | Andy Lutomirski <luto@kernel.org> | 2016-04-02 14:01:38 (GMT) |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-04-13 09:37:46 (GMT) |
| commit | dd2f4a004b016bbfb64f1de49cb45e66232e40a6 (patch) | |
| tree | 8c95610aa558cd7c257c08608c063dec10c9f215 /arch/x86/include/asm/paravirt_types.h | |
| parent | fbd704374d111bed16a19261176fa30e2379c87c (diff) | |
| download | linux-dd2f4a004b016bbfb64f1de49cb45e66232e40a6.tar.xz | |
x86/paravirt: Add paravirt_{read,write}_msr()
This adds paravirt callbacks for unsafe MSR access. On native, they
call native_{read,write}_msr(). On Xen, they use xen_{read,write}_msr_safe().
Nothing uses them yet for ease of bisection. The next patch will
use them in rdmsrl(), wrmsrl(), etc.
I intentionally didn't make them warn on #GP on Xen. I think that
should be done separately by the Xen maintainers.
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: KVM list <kvm@vger.kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel <Xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/880eebc5dcd2ad9f310d41345f82061ea500e9fa.1459605520.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include/asm/paravirt_types.h')
| -rw-r--r-- | arch/x86/include/asm/paravirt_types.h | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 09c9e1d..b4a23ea 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -155,8 +155,14 @@ struct pv_cpu_ops { void (*cpuid)(unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx); - /* MSR operations. - err = 0/-EIO. wrmsr returns 0/-EIO. */ + /* Unsafe MSR operations. These will warn or panic on failure. */ + u64 (*read_msr)(unsigned int msr); + void (*write_msr)(unsigned int msr, unsigned low, unsigned high); + + /* + * Safe MSR operations. + * read sets err to 0 or -EIO. write returns 0 or -EIO. + */ u64 (*read_msr_safe)(unsigned int msr, int *err); int (*write_msr_safe)(unsigned int msr, unsigned low, unsigned high); |