[PATCH] x86/mce: Update bootlog description to reflect behavior on AMD

[PATCH] x86/mce: Update bootlog description to reflect behavior on AMD

[Yazen Ghannam]

From: Yazen Ghannam <yazen.ghannam@amd.com>

The bootlog option is only disabled by default on AMD Fam10h and older
systems.

Update bootlog description to say this.

Change the family value to hex to avoid confusion.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
---
 Documentation/x86/x86_64/boot-options.txt | 3 ++-
 arch/x86/kernel/cpu/mcheck/mce.c          | 5 +++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt
index 61b611e..b297c48 100644
--- a/Documentation/x86/x86_64/boot-options.txt
+++ b/Documentation/x86/x86_64/boot-options.txt
@@ -36,7 +36,8 @@ Machine check
 		to broadcast MCEs.
    mce=bootlog
 		Enable logging of machine checks left over from booting.
-		Disabled by default on AMD because some BIOS leave bogus ones.
+		Disabled by default on AMD Fam10h and older because some BIOS
+		leave bogus ones.
 		If your BIOS doesn't do that it's a good idea to enable though
 		to make sure you log even machine check events that result
 		in a reboot. On Intel systems it is enabled by default.
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index e317a95..fa09d41 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1550,7 +1550,7 @@ static int __mcheck_cpu_apply_quirks(struct cpuinfo_x86 *c)
 			 */
 			clear_bit(10, (unsigned long *)&mce_banks[4].ctl);
 		}
-		if (c->x86 < 17 && cfg->bootlog < 0) {
+		if (c->x86 < 0x11 && cfg->bootlog < 0) {
 			/*
 			 * Lots of broken BIOS around that don't clear them
 			 * by default and leave crap in there. Don't log:
@@ -1832,7 +1832,8 @@ void mce_disable_bank(int bank)
  * mce=TOLERANCELEVEL[,monarchtimeout] (number, see above)
  *	monarchtimeout is how long to wait for other CPUs on machine
  *	check, or 0 to not wait
- * mce=bootlog Log MCEs from before booting. Disabled by default on AMD.
+ * mce=bootlog Log MCEs from before booting. Disabled by default on AMD Fam10h
+	and older.
  * mce=nobootlog Don't log MCEs from before booting.
  * mce=bios_cmci_threshold Don't program the CMCI threshold
  * mce=recovery force enable memcpy_mcsafe()
-- 
2.7.4

Re: [PATCH] x86/mce: Update bootlog description to reflect behavior on AMD

[Borislav Petkov]

On Fri, Jun 09, 2017 at 02:40:44PM -0500, Yazen Ghannam wrote:
> From: Yazen Ghannam <yazen.ghannam@amd.com>
> 
> The bootlog option is only disabled by default on AMD Fam10h and older
> systems.
> 
> Update bootlog description to say this.
> 
> Change the family value to hex to avoid confusion.
> 
> Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
> ---
>  Documentation/x86/x86_64/boot-options.txt | 3 ++-
>  arch/x86/kernel/cpu/mcheck/mce.c          | 5 +++--
>  2 files changed, 5 insertions(+), 3 deletions(-)

Applied, thanks.

-- 
Regards/Gruss,
    Boris.

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