mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-28 15:20:41 +00:00
Code Issues Releases Wiki Activity

x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y

Browse source 
Enabling CONFIG_PARAVIRT had an unintended side effect: rdmsr() turned
into rdmsr_safe() and wrmsr() turned into wrmsr_safe(), even on bare
metal.  Undo that by using the new unsafe paravirt MSR callbacks.

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/414fabd6d3527703077c6c2a797223d0a9c3b081.1459605520.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Andy Lutomirski 2016-04-02 07:01:39 -07:00 committed by Ingo Molnar
parent dd2f4a004b
commit 4985ce15a3
1 changed files with 3 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
arch/x86/include/asm/paravirt.h
View file

@ -152,24 +152,21 @@ static inline int paravirt_write_msr_safe(unsigned msr,
return PVOP_CALL3(int, pv_cpu_ops.write_msr_safe, msr, low, high);
}
/* These should all do BUG_ON(_err), but our headers are too tangled. */
#define rdmsr(msr, val1, val2) \
do { \
int _err; \
u64 _l = paravirt_read_msr_safe(msr, &_err); \
u64 _l = paravirt_read_msr(msr); \
val1 = (u32)_l; \
val2 = _l >> 32; \
} while (0)
#define wrmsr(msr, val1, val2) \
do { \
paravirt_write_msr_safe(msr, val1, val2); \
paravirt_write_msr(msr, val1, val2); \
} while (0)
#define rdmsrl(msr, val) \
do { \
int _err; \
val = paravirt_read_msr_safe(msr, &_err); \
val = paravirt_read_msr(msr); \
} while (0)
static inline void wrmsrl(unsigned msr, u64 val)