Re: [PATCH] x86/cpu: Fix SMAP check in PVOPS environments
From: Rusty Russell
Date: Thu Jun 04 2015 - 22:58:46 EST
"H. Peter Anvin" <hpa@xxxxxxxxx> writes:
> On 06/04/2015 12:55 PM, Rusty Russell wrote:
>>
>> Yeah, hard cases make bad law.
>>
>> I'm not too unhappy with this fix; ideally we'd rename save_fl and
>> restore_fl to save_eflags_if and restore_eflags_if too.
>>
>
> I would be fine with this... but please document what the bloody
> semantics of pvops is actually supposed to be.
*cough*.
Lightly compile tested...
Subject: x86: rename save_fl/restore_fl paravirt ops to highlight eflags.
From: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
As the comment in arch/x86/include/asm/paravirt_types.h says:
* Get/set interrupt state. save_fl and restore_fl are only
* expected to use X86_EFLAGS_IF; all other bits
* returned from save_fl are undefined, and may be ignored by
* restore_fl.
Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 8957810ad7d1..5ad7b0e62a77 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -801,12 +801,12 @@ static __always_inline void __ticket_unlock_kick(struct arch_spinlock *lock,
static inline notrace unsigned long arch_local_save_flags(void)
{
- return PVOP_CALLEE0(unsigned long, pv_irq_ops.save_fl);
+ return PVOP_CALLEE0(unsigned long, pv_irq_ops.save_eflags_if);
}
static inline notrace void arch_local_irq_restore(unsigned long f)
{
- PVOP_VCALLEE1(pv_irq_ops.restore_fl, f);
+ PVOP_VCALLEE1(pv_irq_ops.restore_eflags_if, f);
}
static inline notrace void arch_local_irq_disable(void)
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index f7b0b5c112f2..05425c8544f1 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -204,8 +204,8 @@ struct pv_irq_ops {
* NOTE: These functions callers expect the callee to preserve
* more registers than the standard C calling convention.
*/
- struct paravirt_callee_save save_fl;
- struct paravirt_callee_save restore_fl;
+ struct paravirt_callee_save save_eflags_if;
+ struct paravirt_callee_save restore_eflags_if;
struct paravirt_callee_save irq_disable;
struct paravirt_callee_save irq_enable;
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index c614dd492f5f..d42e33b66ee6 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -321,8 +321,8 @@ struct pv_time_ops pv_time_ops = {
};
__visible struct pv_irq_ops pv_irq_ops = {
- .save_fl = __PV_IS_CALLEE_SAVE(native_save_fl),
- .restore_fl = __PV_IS_CALLEE_SAVE(native_restore_fl),
+ .save_eflags_if = __PV_IS_CALLEE_SAVE(native_save_fl),
+ .restore_eflags_if = __PV_IS_CALLEE_SAVE(native_restore_fl),
.irq_disable = __PV_IS_CALLEE_SAVE(native_irq_disable),
.irq_enable = __PV_IS_CALLEE_SAVE(native_irq_enable),
.safe_halt = native_safe_halt,
diff --git a/arch/x86/kernel/paravirt_patch_32.c b/arch/x86/kernel/paravirt_patch_32.c
index d9f32e6d6ab6..cf20c1b37f43 100644
--- a/arch/x86/kernel/paravirt_patch_32.c
+++ b/arch/x86/kernel/paravirt_patch_32.c
@@ -2,8 +2,8 @@
DEF_NATIVE(pv_irq_ops, irq_disable, "cli");
DEF_NATIVE(pv_irq_ops, irq_enable, "sti");
-DEF_NATIVE(pv_irq_ops, restore_fl, "push %eax; popf");
-DEF_NATIVE(pv_irq_ops, save_fl, "pushf; pop %eax");
+DEF_NATIVE(pv_irq_ops, restore_eflags_if, "push %eax; popf");
+DEF_NATIVE(pv_irq_ops, save_eflags_if, "pushf; pop %eax");
DEF_NATIVE(pv_cpu_ops, iret, "iret");
DEF_NATIVE(pv_cpu_ops, irq_enable_sysexit, "sti; sysexit");
DEF_NATIVE(pv_mmu_ops, read_cr2, "mov %cr2, %eax");
@@ -38,8 +38,8 @@ unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
switch (type) {
PATCH_SITE(pv_irq_ops, irq_disable);
PATCH_SITE(pv_irq_ops, irq_enable);
- PATCH_SITE(pv_irq_ops, restore_fl);
- PATCH_SITE(pv_irq_ops, save_fl);
+ PATCH_SITE(pv_irq_ops, restore_eflags_if);
+ PATCH_SITE(pv_irq_ops, save_eflags_if);
PATCH_SITE(pv_cpu_ops, iret);
PATCH_SITE(pv_cpu_ops, irq_enable_sysexit);
PATCH_SITE(pv_mmu_ops, read_cr2);
diff --git a/arch/x86/kernel/paravirt_patch_64.c b/arch/x86/kernel/paravirt_patch_64.c
index a1da6737ba5b..24eaaa5f9aa6 100644
--- a/arch/x86/kernel/paravirt_patch_64.c
+++ b/arch/x86/kernel/paravirt_patch_64.c
@@ -4,8 +4,8 @@
DEF_NATIVE(pv_irq_ops, irq_disable, "cli");
DEF_NATIVE(pv_irq_ops, irq_enable, "sti");
-DEF_NATIVE(pv_irq_ops, restore_fl, "pushq %rdi; popfq");
-DEF_NATIVE(pv_irq_ops, save_fl, "pushfq; popq %rax");
+DEF_NATIVE(pv_irq_ops, restore_eflags_if, "pushq %rdi; popfq");
+DEF_NATIVE(pv_irq_ops, save_eflags_if, "pushfq; popq %rax");
DEF_NATIVE(pv_mmu_ops, read_cr2, "movq %cr2, %rax");
DEF_NATIVE(pv_mmu_ops, read_cr3, "movq %cr3, %rax");
DEF_NATIVE(pv_mmu_ops, write_cr3, "movq %rdi, %cr3");
@@ -45,8 +45,8 @@ unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
end = end_##ops##_##x; \
goto patch_site
switch(type) {
- PATCH_SITE(pv_irq_ops, restore_fl);
- PATCH_SITE(pv_irq_ops, save_fl);
+ PATCH_SITE(pv_irq_ops, restore_eflags_if);
+ PATCH_SITE(pv_irq_ops, save_eflags_if);
PATCH_SITE(pv_irq_ops, irq_enable);
PATCH_SITE(pv_irq_ops, irq_disable);
PATCH_SITE(pv_cpu_ops, irq_enable_sysexit);
diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
index ee22c1d93ae5..c7f09f3fb31d 100644
--- a/arch/x86/kernel/vsmp_64.c
+++ b/arch/x86/kernel/vsmp_64.c
@@ -78,8 +78,8 @@ static unsigned __init_or_module vsmp_patch(u8 type, u16 clobbers, void *ibuf,
switch (type) {
case PARAVIRT_PATCH(pv_irq_ops.irq_enable):
case PARAVIRT_PATCH(pv_irq_ops.irq_disable):
- case PARAVIRT_PATCH(pv_irq_ops.save_fl):
- case PARAVIRT_PATCH(pv_irq_ops.restore_fl):
+ case PARAVIRT_PATCH(pv_irq_ops.save_eflags_if):
+ case PARAVIRT_PATCH(pv_irq_ops.restore_eflags_if):
return paravirt_patch_default(type, clobbers, ibuf, addr, len);
default:
return native_patch(type, clobbers, ibuf, addr, len);
@@ -119,8 +119,8 @@ static void __init set_vsmp_pv_ops(void)
/* Setup irq ops and turn on vSMP IRQ fastpath handling */
pv_irq_ops.irq_disable = PV_CALLEE_SAVE(vsmp_irq_disable);
pv_irq_ops.irq_enable = PV_CALLEE_SAVE(vsmp_irq_enable);
- pv_irq_ops.save_fl = PV_CALLEE_SAVE(vsmp_save_fl);
- pv_irq_ops.restore_fl = PV_CALLEE_SAVE(vsmp_restore_fl);
+ pv_irq_ops.save_eflags_if = PV_CALLEE_SAVE(vsmp_save_fl);
+ pv_irq_ops.restore_eflags_if = PV_CALLEE_SAVE(vsmp_restore_fl);
pv_init_ops.patch = vsmp_patch;
ctl &= ~(1 << 4);
}
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 8f9a133cc099..5f35bf3ff0b0 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -1426,8 +1426,8 @@ __init void lguest_init(void)
*/
/* Interrupt-related operations */
- pv_irq_ops.save_fl = PV_CALLEE_SAVE(lguest_save_fl);
- pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(lg_restore_fl);
+ pv_irq_ops.save_eflags_if = PV_CALLEE_SAVE(lguest_save_fl);
+ pv_irq_ops.restore_eflags_if = __PV_IS_CALLEE_SAVE(lg_restore_fl);
pv_irq_ops.irq_disable = PV_CALLEE_SAVE(lguest_irq_disable);
pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(lg_irq_enable);
pv_irq_ops.safe_halt = lguest_safe_halt;
diff --git a/arch/x86/lguest/head_32.S b/arch/x86/lguest/head_32.S
index d5ae63f5ec5d..03b94d38fbd7 100644
--- a/arch/x86/lguest/head_32.S
+++ b/arch/x86/lguest/head_32.S
@@ -64,7 +64,7 @@ LGUEST_PATCH(pushf, movl lguest_data+LGUEST_DATA_irq_enabled, %eax)
/*G:033
* But using those wrappers is inefficient (we'll see why that doesn't matter
- * for save_fl and irq_disable later). If we write our routines carefully in
+ * for lguest_save_fl and irq_disable later). If we write our routines carefully in
* assembler, we can avoid clobbering any registers and avoid jumping through
* the wrapper functions.
*
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 46957ead3060..d9511df0d63c 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1074,8 +1074,8 @@ void xen_setup_vcpu_info_placement(void)
* percpu area for all cpus, so make use of it. Note that for
* PVH we want to use native IRQ mechanism. */
if (have_vcpu_info_placement && !xen_pvh_domain()) {
- pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
- pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
+ pv_irq_ops.save_eflags_if = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
+ pv_irq_ops.restore_eflags_if = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
@@ -1102,8 +1102,8 @@ static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
switch (type) {
SITE(pv_irq_ops, irq_enable);
SITE(pv_irq_ops, irq_disable);
- SITE(pv_irq_ops, save_fl);
- SITE(pv_irq_ops, restore_fl);
+ SITE(pv_irq_ops, save_eflags_if);
+ SITE(pv_irq_ops, restore_eflags_if);
#undef SITE
patch_site:
diff --git a/arch/x86/xen/irq.c b/arch/x86/xen/irq.c
index a1207cb6472a..a7f58c48c2e1 100644
--- a/arch/x86/xen/irq.c
+++ b/arch/x86/xen/irq.c
@@ -115,8 +115,8 @@ static void xen_halt(void)
}
static const struct pv_irq_ops xen_irq_ops __initconst = {
- .save_fl = PV_CALLEE_SAVE(xen_save_fl),
- .restore_fl = PV_CALLEE_SAVE(xen_restore_fl),
+ .save_eflags_if = PV_CALLEE_SAVE(xen_save_fl),
+ .restore_eflags_if = PV_CALLEE_SAVE(xen_restore_fl),
.irq_disable = PV_CALLEE_SAVE(xen_irq_disable),
.irq_enable = PV_CALLEE_SAVE(xen_irq_enable),
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/