x86, mce: fix boot logging logic

The earlier patch to change the poller to a separate function subtly
broke the boot logging logic. This could lead to machine checks
getting logged at boot even when disabled or defaulting to off
on some systems. Fix that.

[ Impact: bug fix - avoid spurious MCE in log ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 563933e06a35fa48f6c828d3884f9b35886ab4eb..4f8c199584e748c8075a1fd4c344f7af9d33688e 100644 (file)
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -137,6 +137,7 @@ DECLARE_PER_CPU(mce_banks_t, mce_poll_banks);
 enum mcp_flags {
        MCP_TIMESTAMP = (1 << 0),       /* log time stamp */
        MCP_UC = (1 << 1),              /* log uncorrected errors */
+       MCP_DONTLOG = (1 << 2),         /* only clear, don't log */
 };
 extern void machine_check_poll(enum mcp_flags flags, mce_banks_t *b);
 

diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c b/arch/x86/kernel/cpu/mcheck/mce_64.c
index 82614f1b923a6069598acea774a7a8fc071dc062..6fb0b359d2a5ead120c59b114a4a8834f297e0a3 100644 (file)
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -239,9 +239,10 @@ void machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
                 * Don't get the IP here because it's unlikely to
                 * have anything to do with the actual error location.
                 */
-
-               mce_log(&m);
-               add_taint(TAINT_MACHINE_CHECK);
+               if (!(flags & MCP_DONTLOG)) {
+                       mce_log(&m);
+                       add_taint(TAINT_MACHINE_CHECK);
+               }
 
                /*
                 * Clear state for this bank.
@@ -585,7 +586,7 @@ static void mce_init(void *dummy)
         * Log the machine checks left over from the previous reset.
         */
        bitmap_fill(all_banks, MAX_NR_BANKS);
-       machine_check_poll(MCP_UC, &all_banks);
+       machine_check_poll(MCP_UC|(!mce_bootlog ? MCP_DONTLOG : 0), &all_banks);
 
        set_in_cr4(X86_CR4_MCE);