linux-kernel - [PATCH 2/7] x86/mcheck: Explicit cleanup on failure in mce

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Date:   Thu, 10 Nov 2016 18:44:42 +0100
From:   Sebastian Andrzej Siewior <bigeasy@...utronix.de>
To:     linux-kernel@...r.kernel.org
Cc:     tglx@...utronix.de, rt@...utronix.de,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        Tony Luck <tony.luck@...el.com>,
        Borislav Petkov <bp@...en8.de>, linux-edac@...r.kernel.org,
        x86@...nel.org
Subject: [PATCH 2/7] x86/mcheck: Explicit cleanup on failure in mce_amd

If the ONLINE callback fails, the driver does not any clean up right
away instead it waits to get to the DEAD stage to do it. Yes, it waits.
Since we don't pass the error code back to the caller, no one knows.

Do the clean up right away so it does not look like a leak.

Cc: Tony Luck <tony.luck@...el.com>
Cc: Borislav Petkov <bp@...en8.de>
Cc: linux-edac@...r.kernel.org
Cc: x86@...nel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
---
 arch/x86/kernel/cpu/mcheck/mce_amd.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index 75a3e3eab81e..55cd018bc1ae 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -1087,6 +1087,7 @@ static void threshold_remove_device(unsigned int cpu)
 		threshold_remove_bank(cpu, bank);
 	}
 	kfree(per_cpu(threshold_banks, cpu));
+	per_cpu(threshold_banks, cpu) = NULL;
 }
 
 /* create dir/files for all valid threshold banks */
@@ -1108,9 +1109,11 @@ static int threshold_create_device(unsigned int cpu)
 			continue;
 		err = threshold_create_bank(cpu, bank);
 		if (err)
-			return err;
+			goto err;
 	}
-
+	return err;
+err:
+	threshold_remove_device(cpu);
 	return err;
 }
 
-- 
2.10.2