[PATCH 3/3] x86/MCE/AMD: Get address from already initialized block

Yazen Ghannam
2018-02-01T18:49:02Z

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

The block address is saved after the block is initialized when
threshold_init_device() is called.

Use the saved block address, if available, rather than trying to
rediscover it.

We can avoid some *on_cpu() calls in the init path that will cause a
call trace when resuming from suspend.

Cc: <stable@vger.kernel.org> # 4.14.x
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
---
arch/x86/kernel/cpu/mcheck/mce_amd.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index bf53b4549a17..8c4f8f30c779 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -436,6 +436,21 @@ static u32 get_block_address(unsigned int cpu, u32 current_addr, u32 low, u32 hi
{
u32 addr = 0, offset = 0;

+ if ((bank >= mca_cfg.banks) || (block >= NR_BLOCKS))
+ return addr;
+
+ /* Get address from already initialized block. */
+ if (per_cpu(threshold_banks, cpu)) {
+ struct threshold_bank *bankp = per_cpu(threshold_banks, cpu)[bank];
+
+ if (bankp && bankp->blocks) {
+ struct threshold_block *blockp = &bankp->blocks[block];
+
+ if (blockp)
+ return blockp->address;
+ }
+ }
+
if (mce_flags.smca) {
if (smca_get_bank_type(bank) == SMCA_RESERVED)
return addr;
--
2.14.1