Commit 68627a69 authored by Yazen Ghannam's avatar Yazen Ghannam Committed by Ingo Molnar
Browse files

x86/mce/AMD, EDAC/mce_amd: Enumerate Reserved SMCA bank type 



Currently, bank 4 is reserved on Fam17h, so we chose not to initialize
bank 4 in the smca_banks array. This means that when we check if a bank
is initialized, like during boot or resume, we will see that bank 4 is
not initialized and try to initialize it.

This will cause a call trace, when resuming from suspend, due to
rdmsr_*on_cpu() calls in the init path. The rdmsr_*on_cpu() calls issue
an IPI but we're running with interrupts disabled. This triggers:

  WARNING: CPU: 0 PID: 11523 at kernel/smp.c:291 smp_call_function_single+0xdc/0xe0
  ...

Reserved banks will be read-as-zero, so their MCA_IPID register will be
zero. So, like the smca_banks array, the threshold_banks array will not
have an entry for a reserved bank since all its MCA_MISC* registers will
be zero.

Enumerate a "Reserved" bank type that matches on a HWID_MCATYPE of 0,0.

Use the "Reserved" type when checking if a bank is reserved. It's
possible that other bank numbers may be reserved on future systems.

Don't try to find the block address on reserved banks.

Signed-off-by: default avatarYazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org> # 4.14.x
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20180221101900.10326-7-bp@alien8.de


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent e5d6a126

arch/x86/include/asm/mce.h

+1 −0
Original line number Diff line number Diff line
@@ -294,6 +294,7 @@ enum smca_bank_types { 
	SMCA_IF,	/* Instruction Fetch */

	SMCA_L2_CACHE,	/* L2 Cache */

	SMCA_DE,	/* Decoder Unit */

	SMCA_RESERVED,	/* Reserved */

	SMCA_EX,	/* Execution Unit */

	SMCA_FP,	/* Floating Point */

	SMCA_L3_CACHE,	/* L3 Cache */

arch/x86/kernel/cpu/mcheck/mce_amd.c

+7 −0
Original line number Diff line number Diff line
@@ -82,6 +82,7 @@ static struct smca_bank_name smca_names[] = { 
	[SMCA_IF]	= { "insn_fetch",	"Instruction Fetch Unit" },

	[SMCA_L2_CACHE]	= { "l2_cache",		"L2 Cache" },

	[SMCA_DE]	= { "decode_unit",	"Decode Unit" },

	[SMCA_RESERVED]	= { "reserved",		"Reserved" },

	[SMCA_EX]	= { "execution_unit",	"Execution Unit" },

	[SMCA_FP]	= { "floating_point",	"Floating Point Unit" },

	[SMCA_L3_CACHE]	= { "l3_cache",		"L3 Cache" },
@@ -127,6 +128,9 @@ static enum smca_bank_types smca_get_bank_type(unsigned int bank) 
static struct smca_hwid smca_hwid_mcatypes[] = {

	/* { bank_type, hwid_mcatype, xec_bitmap } */



	/* Reserved type */

	{ SMCA_RESERVED, HWID_MCATYPE(0x00, 0x0), 0x0 },



	/* ZN Core (HWID=0xB0) MCA types */

	{ SMCA_LS,	 HWID_MCATYPE(0xB0, 0x0), 0x1FFFEF },

	{ SMCA_IF,	 HWID_MCATYPE(0xB0, 0x1), 0x3FFF },
@@ -433,6 +437,9 @@ static u32 get_block_address(unsigned int cpu, u32 current_addr, u32 low, u32 hi 
	u32 addr = 0, offset = 0;



	if (mce_flags.smca) {

		if (smca_get_bank_type(bank) == SMCA_RESERVED)

			return addr;



		if (!block) {

			addr = MSR_AMD64_SMCA_MCx_MISC(bank);

		} else {

drivers/edac/mce_amd.c

+7 −4
Original line number Diff line number Diff line
@@ -854,21 +854,24 @@ static void decode_mc6_mce(struct mce *m) 
static void decode_smca_error(struct mce *m)

{

	struct smca_hwid *hwid;

	unsigned int bank_type;

	enum smca_bank_types bank_type;

	const char *ip_name;

	u8 xec = XEC(m->status, xec_mask);



	if (m->bank >= ARRAY_SIZE(smca_banks))

		return;



	if (x86_family(m->cpuid) >= 0x17 && m->bank == 4)

		pr_emerg(HW_ERR "Bank 4 is reserved on Fam17h.\n");



	hwid = smca_banks[m->bank].hwid;

	if (!hwid)

		return;



	bank_type = hwid->bank_type;



	if (bank_type == SMCA_RESERVED) {

		pr_emerg(HW_ERR "Bank %d is reserved.\n", m->bank);

		return;

	}



	ip_name = smca_get_long_name(bank_type);



	pr_emerg(HW_ERR "%s Extended Error Code: %d\n", ip_name, xec);

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