[PATCH v2 0/1] x86/mce: correct the detection of invalid mce priorities

[PATCH v2 0/1] x86/mce: correct the detection of invalid mce priorities

[Zhen Lei]

v1 --> v2:
Update the detection of invalid mce priorities, the WARN_ON() is needed.

v1:
Remove the WARN_ON() in mce_register_decode_chain().

Zhen Lei (1):
  x86/mce: correct the detection of invalid mce priorities

 arch/x86/include/asm/mce.h     | 3 ++-
 arch/x86/kernel/cpu/mce/core.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

-- 
2.26.0.106.g9fadedd

[PATCH v2 1/1] x86/mce: correct the detection of invalid mce priorities

[Zhen Lei]

enum mce_notifier_prios {
	MCE_PRIO_LOWEST,
	...
	MCE_PRIO_CEC
};

After commit c9c6d216ed28 ("x86/mce: Rename "first" function as "early""),
the range of invalid priorities is changed. Add a new enumeration value
MCE_PRIO_HIGHEST, so that people can add enumeration values greater than
MCE_PRIO_CEC in the future without having to modify the function
mce_register_decode_chain().

Because the type of "nb->priority" is int, so the priority less than
MCE_PRIO_LOWEST is also invalid.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
---
 arch/x86/include/asm/mce.h     | 3 ++-
 arch/x86/kernel/cpu/mce/core.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index a0f147893a04..fc25c88c7ff2 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -177,7 +177,8 @@ enum mce_notifier_prios {
 	MCE_PRIO_EXTLOG,
 	MCE_PRIO_UC,
 	MCE_PRIO_EARLY,
-	MCE_PRIO_CEC
+	MCE_PRIO_CEC,
+	MCE_PRIO_HIGHEST = MCE_PRIO_CEC
 };
 
 struct notifier_block;
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 4102b866e7c0..0a54a2cfeeff 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -162,7 +162,8 @@ EXPORT_SYMBOL_GPL(mce_log);
 
 void mce_register_decode_chain(struct notifier_block *nb)
 {
-	if (WARN_ON(nb->priority > MCE_PRIO_MCELOG && nb->priority < MCE_PRIO_EDAC))
+	if (WARN_ON((nb->priority < MCE_PRIO_LOWEST) ||
+		    (nb->priority > MCE_PRIO_HIGHEST)))
 		return;
 
 	blocking_notifier_chain_register(&x86_mce_decoder_chain, nb);
-- 
2.26.0.106.g9fadedd

[tip: ras/core] x86/mce: Correct the detection of invalid notifier priorities

[tip-bot2 for Zhen Lei]

The following commit has been merged into the ras/core branch of tip:

Commit-ID:     15af36596ae305aefc8c502c2d3e8c58221709eb
Gitweb:        https://git.kernel.org/tip/15af36596ae305aefc8c502c2d3e8c58221709eb
Author:        Zhen Lei <thunder.leizhen@huawei.com>
AuthorDate:    Fri, 06 Nov 2020 22:12:16 +08:00
Committer:     Borislav Petkov <bp@suse.de>
CommitterDate: Fri, 06 Nov 2020 19:02:48 +01:00

x86/mce: Correct the detection of invalid notifier priorities

Commit

  c9c6d216ed28 ("x86/mce: Rename "first" function as "early"")

changed the enumeration of MCE notifier priorities. Correct the check
for notifier priorities to cover the new range.

 [ bp: Rewrite commit message, remove superfluous brackets in
   conditional. ]

Fixes: c9c6d216ed28 ("x86/mce: Rename "first" function as "early"")
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201106141216.2062-2-thunder.leizhen@huawei.com
---
 arch/x86/include/asm/mce.h     | 3 ++-
 arch/x86/kernel/cpu/mce/core.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index a0f1478..fc25c88 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -177,7 +177,8 @@ enum mce_notifier_prios {
 	MCE_PRIO_EXTLOG,
 	MCE_PRIO_UC,
 	MCE_PRIO_EARLY,
-	MCE_PRIO_CEC
+	MCE_PRIO_CEC,
+	MCE_PRIO_HIGHEST = MCE_PRIO_CEC
 };
 
 struct notifier_block;
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 888248a..ccac4c2 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -162,7 +162,8 @@ EXPORT_SYMBOL_GPL(mce_log);
 
 void mce_register_decode_chain(struct notifier_block *nb)
 {
-	if (WARN_ON(nb->priority > MCE_PRIO_MCELOG && nb->priority < MCE_PRIO_EDAC))
+	if (WARN_ON(nb->priority < MCE_PRIO_LOWEST ||
+		    nb->priority > MCE_PRIO_HIGHEST))
 		return;
 
 	blocking_notifier_chain_register(&x86_mce_decoder_chain, nb);