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x86/paravirt: Use normal calling sequences for irq enable/disable

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Bastian Blank reported a boot crash with stackprotector enabled,
and debugged it back to edx register corruption.

For historical reasons irq enable/disable/save/restore had special
calling sequences to make them more efficient.  With the more
recent introduction of higher-level and more general optimisations
this is no longer necessary so we can just use the normal PVOP_
macros.

This fixes some residual bugs in the old implementations which left
edx liable to inadvertent clobbering. Also, fix some bugs in
__PVOP_VCALLEESAVE which were revealed by actual use.

Reported-by: Bastian Blank <bastian@waldi.eu.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: Xen-devel <xen-devel@lists.xensource.com>
LKML-Reference: <4AD3BC9B.7040501@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Jeremy Fitzhardinge 2009-10-12 16:32:43 -07:00 committed by Ingo Molnar
parent d1705c558c
commit 71999d9862
2 changed files with 10 additions and 28 deletions
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28
arch/x86/include/asm/paravirt.h
View File

@ -840,42 +840,22 @@ static __always_inline void __raw_spin_unlock(struct raw_spinlock *lock)
static inline unsigned long __raw_local_save_flags(void)
{
unsigned long f;
asm volatile(paravirt_alt(PARAVIRT_CALL)
: "=a"(f)
: paravirt_type(pv_irq_ops.save_fl),
paravirt_clobber(CLBR_EAX)
: "memory", "cc");
return f;
return PVOP_CALLEE0(unsigned long, pv_irq_ops.save_fl);
}
static inline void raw_local_irq_restore(unsigned long f)
{
asm volatile(paravirt_alt(PARAVIRT_CALL)
: "=a"(f)
: PV_FLAGS_ARG(f),
paravirt_type(pv_irq_ops.restore_fl),
paravirt_clobber(CLBR_EAX)
: "memory", "cc");
PVOP_VCALLEE1(pv_irq_ops.restore_fl, f);
}
static inline void raw_local_irq_disable(void)
{
asm volatile(paravirt_alt(PARAVIRT_CALL)
:
: paravirt_type(pv_irq_ops.irq_disable),
paravirt_clobber(CLBR_EAX)
: "memory", "eax", "cc");
PVOP_VCALLEE0(pv_irq_ops.irq_disable);
}
static inline void raw_local_irq_enable(void)
{
asm volatile(paravirt_alt(PARAVIRT_CALL)
:
: paravirt_type(pv_irq_ops.irq_enable),
paravirt_clobber(CLBR_EAX)
: "memory", "eax", "cc");
PVOP_VCALLEE0(pv_irq_ops.irq_enable);
}
static inline unsigned long __raw_local_irq_save(void)

10
arch/x86/include/asm/paravirt_types.h
View File

@ -494,10 +494,11 @@ int paravirt_disable_iospace(void);
#define EXTRA_CLOBBERS
#define VEXTRA_CLOBBERS
#else /* CONFIG_X86_64 */
/* [re]ax isn't an arg, but the return val */
#define PVOP_VCALL_ARGS \
unsigned long __edi = __edi, __esi = __esi, \
__edx = __edx, __ecx = __ecx
#define PVOP_CALL_ARGS PVOP_VCALL_ARGS, __eax
__edx = __edx, __ecx = __ecx, __eax = __eax
#define PVOP_CALL_ARGS PVOP_VCALL_ARGS
#define PVOP_CALL_ARG1(x) "D" ((unsigned long)(x))
#define PVOP_CALL_ARG2(x) "S" ((unsigned long)(x))
@ -509,6 +510,7 @@ int paravirt_disable_iospace(void);
"=c" (__ecx)
#define PVOP_CALL_CLOBBERS PVOP_VCALL_CLOBBERS, "=a" (__eax)
/* void functions are still allowed [re]ax for scratch */
#define PVOP_VCALLEE_CLOBBERS "=a" (__eax)
#define PVOP_CALLEE_CLOBBERS PVOP_VCALLEE_CLOBBERS
@ -583,8 +585,8 @@ int paravirt_disable_iospace(void);
VEXTRA_CLOBBERS, \
pre, post, ##__VA_ARGS__)
#define __PVOP_VCALLEESAVE(rettype, op, pre, post, ...) \
____PVOP_CALL(rettype, op.func, CLBR_RET_REG, \
#define __PVOP_VCALLEESAVE(op, pre, post, ...) \
____PVOP_VCALL(op.func, CLBR_RET_REG, \
PVOP_VCALLEE_CLOBBERS, , \
pre, post, ##__VA_ARGS__)