[PATCH] x86: correct saving and restoring of lapic vectors in suspend/resume

[PATCH] x86: correct saving and restoring of lapic vectors in suspend/resume

[Juergen Gross]

Saving and restoring lapic vectors in lapic_suspend() and
lapic_resume() is not consistent: the thmr vector saving is guarded
by a different config option than the restore part. The cmci vector
isn't handled at all.

Those inconsistencies are not very critical, as the missing cmci
vector will be set via mce resume handling, the wrong config option
used for restoring the thmr vector can't be configured differently
than the one which should be used.

Nevertheless correct the thmr vector restore and add cmci vector
handling.

Signed-off-by: Juergen Gross <jgross@suse.com>
---
 arch/x86/kernel/apic/apic.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 2f69e3b..bc06c9d 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2270,6 +2270,7 @@ static struct {
 	unsigned int apic_tmict;
 	unsigned int apic_tdcr;
 	unsigned int apic_thmr;
+	unsigned int apic_cmci;
 } apic_pm_state;
 
 static int lapic_suspend(void)
@@ -2299,6 +2300,10 @@ static int lapic_suspend(void)
 	if (maxlvt >= 5)
 		apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
 #endif
+#ifdef CONFIG_X86_MCE_INTEL
+	if (maxlvt >= 6)
+		apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
+#endif
 
 	local_irq_save(flags);
 	disable_local_APIC();
@@ -2355,10 +2360,14 @@ static void lapic_resume(void)
 	apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
 	apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
 	apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
-#if defined(CONFIG_X86_MCE_INTEL)
+#if defined(CONFIG_X86_THERMAL_VECTOR)
 	if (maxlvt >= 5)
 		apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
 #endif
+#if defined(CONFIG_X86_MCE_INTEL)
+	if (maxlvt >= 6)
+		apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
+#endif
 	if (maxlvt >= 4)
 		apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
 	apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
-- 
2.6.2

Re: [PATCH] x86: correct saving and restoring of lapic vectors in suspend/resume

[Borislav Petkov]

On Mon, Nov 23, 2015 at 11:59:24AM +0100, Juergen Gross wrote:
> Saving and restoring lapic vectors in lapic_suspend() and
> lapic_resume() is not consistent: the thmr vector saving is guarded
> by a different config option than the restore part. The cmci vector
> isn't handled at all.
> 
> Those inconsistencies are not very critical, as the missing cmci
> vector will be set via mce resume handling, the wrong config option
> used for restoring the thmr vector can't be configured differently
> than the one which should be used.
> 
> Nevertheless correct the thmr vector restore and add cmci vector
> handling.
> 
> Signed-off-by: Juergen Gross <jgross@suse.com>
> ---
>  arch/x86/kernel/apic/apic.c | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)

Acked-by: Borislav Petkov <bp@suse.de>

Add Tony to CC and leave in the rest for him to look at:

> diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
> index 2f69e3b..bc06c9d 100644
> --- a/arch/x86/kernel/apic/apic.c
> +++ b/arch/x86/kernel/apic/apic.c
> @@ -2270,6 +2270,7 @@ static struct {
>  	unsigned int apic_tmict;
>  	unsigned int apic_tdcr;
>  	unsigned int apic_thmr;
> +	unsigned int apic_cmci;
>  } apic_pm_state;
>  
>  static int lapic_suspend(void)
> @@ -2299,6 +2300,10 @@ static int lapic_suspend(void)
>  	if (maxlvt >= 5)
>  		apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
>  #endif
> +#ifdef CONFIG_X86_MCE_INTEL
> +	if (maxlvt >= 6)
> +		apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
> +#endif
>  
>  	local_irq_save(flags);
>  	disable_local_APIC();
> @@ -2355,10 +2360,14 @@ static void lapic_resume(void)
>  	apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
>  	apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
>  	apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
> -#if defined(CONFIG_X86_MCE_INTEL)
> +#if defined(CONFIG_X86_THERMAL_VECTOR)
>  	if (maxlvt >= 5)
>  		apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
>  #endif
> +#if defined(CONFIG_X86_MCE_INTEL)
> +	if (maxlvt >= 6)
> +		apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
> +#endif
>  	if (maxlvt >= 4)
>  		apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
>  	apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
> -- 
> 2.6.2
> 
> --
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> 

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.

[tip:x86/apic] x86/apic: Fix the saving and restoring of lapic vectors during suspend/resume

[tip-bot for Juergen Gross]

Commit-ID:  42baa2581c92f8d07e7260506c8d41caf14b0fc3
Gitweb:     http://git.kernel.org/tip/42baa2581c92f8d07e7260506c8d41caf14b0fc3
Author:     Juergen Gross <jgross@suse.com>
AuthorDate: Mon, 23 Nov 2015 11:59:24 +0100
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 24 Nov 2015 09:18:33 +0100

x86/apic: Fix the saving and restoring of lapic vectors during suspend/resume

Saving and restoring lapic vectors in lapic_suspend() and
lapic_resume() is not consistent: the thmr vector saving is
guarded by a different config option than the restore part. The
cmci vector isn't handled at all.

Those inconsistencies are not very critical, as the missing cmci
vector will be set via mce resume handling, the wrong config
option used for restoring the thmr vector can't be configured
differently than the one which should be used.

Nevertheless correct the thmr vector restore and add cmci vector
handling.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1448276364-31334-1-git-send-email-jgross@suse.com
[ Minor code edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 arch/x86/kernel/apic/apic.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 2f69e3b..8d7df74 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2270,6 +2270,7 @@ static struct {
 	unsigned int apic_tmict;
 	unsigned int apic_tdcr;
 	unsigned int apic_thmr;
+	unsigned int apic_cmci;
 } apic_pm_state;
 
 static int lapic_suspend(void)
@@ -2299,6 +2300,10 @@ static int lapic_suspend(void)
 	if (maxlvt >= 5)
 		apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
 #endif
+#ifdef CONFIG_X86_MCE_INTEL
+	if (maxlvt >= 6)
+		apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
+#endif
 
 	local_irq_save(flags);
 	disable_local_APIC();
@@ -2355,10 +2360,14 @@ static void lapic_resume(void)
 	apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
 	apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
 	apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
-#if defined(CONFIG_X86_MCE_INTEL)
+#ifdef CONFIG_X86_THERMAL_VECTOR
 	if (maxlvt >= 5)
 		apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
 #endif
+#ifdef CONFIG_X86_MCE_INTEL
+	if (maxlvt >= 6)
+		apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
+#endif
 	if (maxlvt >= 4)
 		apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
 	apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);