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Commit bafcdd3b authored by Boris Ostrovsky's avatar Boris Ostrovsky Committed by Borislav Petkov
Browse files

x86, MCE, AMD: Use MCG_CAP MSR to find out number of banks on AMD 



Currently number of error reporting register banks is hardcoded to
6 on AMD processors. This may break in virtualized scenarios when
a hypervisor prefers to report fewer banks than what the physical
HW provides.

Since number of supported banks is reported in MSR_IA32_MCG_CAP[7:0]
that's what we should use.

Signed-off-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
Link: http://lkml.kernel.org/r/1363295441-1859-3-git-send-email-boris.ostrovsky@oracle.com


[ reverse NULL ptr test logic ]
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
parent c76e8164

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

+15 −7
Original line number Diff line number Diff line
@@ -33,7 +33,6 @@ 
#include <asm/mce.h>

#include <asm/msr.h>



#define NR_BANKS          6

#define NR_BLOCKS         9

#define THRESHOLD_MAX     0xFFF

#define INT_TYPE_APIC     0x00020000
@@ -57,7 +56,7 @@ static const char * const th_names[] = { 
	"execution_unit",

};



static DEFINE_PER_CPU(struct threshold_bank * [NR_BANKS], threshold_banks);

static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks);

static DEFINE_PER_CPU(unsigned char, bank_map);	/* see which banks are on */



static void amd_threshold_interrupt(void);
@@ -215,7 +214,7 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c) 
	unsigned int bank, block;

	int offset = -1;



	for (bank = 0; bank < NR_BANKS; ++bank) {

	for (bank = 0; bank < mca_cfg.banks; ++bank) {

		for (block = 0; block < NR_BLOCKS; ++block) {

			if (block == 0)

				address = MSR_IA32_MC0_MISC + bank * 4;
@@ -277,7 +276,7 @@ static void amd_threshold_interrupt(void) 
	mce_setup(&m);



	/* assume first bank caused it */

	for (bank = 0; bank < NR_BANKS; ++bank) {

	for (bank = 0; bank < mca_cfg.banks; ++bank) {

		if (!(per_cpu(bank_map, m.cpu) & (1 << bank)))

			continue;

		for (block = 0; block < NR_BLOCKS; ++block) {
@@ -468,7 +467,7 @@ static __cpuinit int allocate_threshold_blocks(unsigned int cpu, 
	u32 low, high;

	int err;



	if ((bank >= NR_BANKS) || (block >= NR_BLOCKS))

	if ((bank >= mca_cfg.banks) || (block >= NR_BLOCKS))

		return 0;



	if (rdmsr_safe_on_cpu(cpu, address, &low, &high))
@@ -636,9 +635,17 @@ static __cpuinit int threshold_create_bank(unsigned int cpu, unsigned int bank) 
static __cpuinit int threshold_create_device(unsigned int cpu)

{

	unsigned int bank;

	struct threshold_bank **bp;

	int err = 0;



	for (bank = 0; bank < NR_BANKS; ++bank) {

	bp = kzalloc(sizeof(struct threshold_bank *) * mca_cfg.banks,

		     GFP_KERNEL);

	if (!bp)

		return -ENOMEM;



	per_cpu(threshold_banks, cpu) = bp;



	for (bank = 0; bank < mca_cfg.banks; ++bank) {

		if (!(per_cpu(bank_map, cpu) & (1 << bank)))

			continue;

		err = threshold_create_bank(cpu, bank);
@@ -720,11 +727,12 @@ static void threshold_remove_device(unsigned int cpu) 
{

	unsigned int bank;



	for (bank = 0; bank < NR_BANKS; ++bank) {

	for (bank = 0; bank < mca_cfg.banks; ++bank) {

		if (!(per_cpu(bank_map, cpu) & (1 << bank)))

			continue;

		threshold_remove_bank(cpu, bank);

	}

	kfree(per_cpu(threshold_banks, cpu));

}



/* get notified when a cpu comes on/off */