[tip: ras/core] x86/mce: Pass pointer to saved pt_regs to severity calculation routines

tip-bot2 for Youquan Song
2020-10-07T10:03:04Z

The following commit has been merged into the ras/core branch of tip:

Commit-ID: 41ce0564bfe2e129d56730418d8c0a9f9f2d31b5
Gitweb: https://git.kernel.org/tip/41ce0564bfe2e129d56730418d8c0a9f9f2d31b5
Author: Youquan Song <youquan.song@intel.com>
AuthorDate: Tue, 06 Oct 2020 14:09:05 -07:00
Committer: Borislav Petkov <bp@suse.de>
CommitterDate: Wed, 07 Oct 2020 10:51:42 +02:00

x86/mce: Pass pointer to saved pt_regs to severity calculation routines

New recovery features require additional information about processor
state when a machine check occurred. Pass pt_regs down to the routines
that need it.

No functional change.

Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-2-tony.luck@intel.com
---
arch/x86/kernel/cpu/mce/core.c | 14 +++++++-------
arch/x86/kernel/cpu/mce/internal.h | 3 ++-
arch/x86/kernel/cpu/mce/severity.c | 14 ++++++++------
3 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index b5b70f4..2d6caf0 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -807,7 +807,7 @@ log_it:
goto clear_it;

mce_read_aux(&m, i);
- m.severity = mce_severity(&m, mca_cfg.tolerant, NULL, false);
+ m.severity = mce_severity(&m, NULL, mca_cfg.tolerant, NULL, false);
/*
* Don't get the IP here because it's unlikely to
* have anything to do with the actual error location.
@@ -856,7 +856,7 @@ static int mce_no_way_out(struct mce *m, char **msg, unsigned long *validp,
quirk_no_way_out(i, m, regs);

m->bank = i;
- if (mce_severity(m, mca_cfg.tolerant, &tmp, true) >= MCE_PANIC_SEVERITY) {
+ if (mce_severity(m, regs, mca_cfg.tolerant, &tmp, true) >= MCE_PANIC_SEVERITY) {
mce_read_aux(m, i);
*msg = tmp;
return 1;
@@ -956,7 +956,7 @@ static void mce_reign(void)
*/
if (m && global_worst >= MCE_PANIC_SEVERITY && mca_cfg.tolerant < 3) {
/* call mce_severity() to get "msg" for panic */
- mce_severity(m, mca_cfg.tolerant, &msg, true);
+ mce_severity(m, NULL, mca_cfg.tolerant, &msg, true);
mce_panic("Fatal machine check", m, msg);
}

@@ -1167,7 +1167,7 @@ static noinstr bool mce_check_crashing_cpu(void)
return false;
}

-static void __mc_scan_banks(struct mce *m, struct mce *final,
+static void __mc_scan_banks(struct mce *m, struct pt_regs *regs, struct mce *final,
unsigned long *toclear, unsigned long *valid_banks,
int no_way_out, int *worst)
{
@@ -1202,7 +1202,7 @@ static void __mc_scan_banks(struct mce *m, struct mce *final,
/* Set taint even when machine check was not enabled. */
add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE);

- severity = mce_severity(m, cfg->tolerant, NULL, true);
+ severity = mce_severity(m, regs, cfg->tolerant, NULL, true);

/*
* When machine check was for corrected/deferred handler don't
@@ -1354,7 +1354,7 @@ noinstr void do_machine_check(struct pt_regs *regs)
order = mce_start(&no_way_out);
}

- __mc_scan_banks(&m, final, toclear, valid_banks, no_way_out, &worst);
+ __mc_scan_banks(&m, regs, final, toclear, valid_banks, no_way_out, &worst);

if (!no_way_out)
mce_clear_state(toclear);
@@ -1376,7 +1376,7 @@ noinstr void do_machine_check(struct pt_regs *regs)
* make sure we have the right "msg".
*/
if (worst >= MCE_PANIC_SEVERITY && mca_cfg.tolerant < 3) {
- mce_severity(&m, cfg->tolerant, &msg, true);
+ mce_severity(&m, regs, cfg->tolerant, &msg, true);
mce_panic("Local fatal machine check!", &m, msg);
}
}
diff --git a/arch/x86/kernel/cpu/mce/internal.h b/arch/x86/kernel/cpu/mce/internal.h
index b122610..88dcc79 100644
--- a/arch/x86/kernel/cpu/mce/internal.h
+++ b/arch/x86/kernel/cpu/mce/internal.h
@@ -38,7 +38,8 @@ int mce_gen_pool_add(struct mce *mce);
int mce_gen_pool_init(void);
struct llist_node *mce_gen_pool_prepare_records(void);

-extern int (*mce_severity)(struct mce *a, int tolerant, char **msg, bool is_excp);
+extern int (*mce_severity)(struct mce *a, struct pt_regs *regs,
+ int tolerant, char **msg, bool is_excp);
struct dentry *mce_get_debugfs_dir(void);

extern mce_banks_t mce_banks_ce_disabled;
diff --git a/arch/x86/kernel/cpu/mce/severity.c b/arch/x86/kernel/cpu/mce/severity.c
index e072246..0b072dc 100644
--- a/arch/x86/kernel/cpu/mce/severity.c
+++ b/arch/x86/kernel/cpu/mce/severity.c
@@ -223,7 +223,7 @@ static struct severity {
* distinguish an exception taken in user from from one
* taken in the kernel.
*/
-static int error_context(struct mce *m)
+static int error_context(struct mce *m, struct pt_regs *regs)
{
if ((m->cs & 3) == 3)
return IN_USER;
@@ -267,9 +267,10 @@ static int mce_severity_amd_smca(struct mce *m, enum context err_ctx)
* See AMD Error Scope Hierarchy table in a newer BKDG. For example
* 49125_15h_Models_30h-3Fh_BKDG.pdf, section "RAS Features"
*/
-static int mce_severity_amd(struct mce *m, int tolerant, char **msg, bool is_excp)
+static int mce_severity_amd(struct mce *m, struct pt_regs *regs, int tolerant,
+ char **msg, bool is_excp)
{
- enum context ctx = error_context(m);
+ enum context ctx = error_context(m, regs);

/* Processor Context Corrupt, no need to fumble too much, die! */
if (m->status & MCI_STATUS_PCC)
@@ -319,10 +320,11 @@ static int mce_severity_amd(struct mce *m, int tolerant, char **msg, bool is_exc
return MCE_KEEP_SEVERITY;
}

-static int mce_severity_intel(struct mce *m, int tolerant, char **msg, bool is_excp)
+static int mce_severity_intel(struct mce *m, struct pt_regs *regs,
+ int tolerant, char **msg, bool is_excp)
{
enum exception excp = (is_excp ? EXCP_CONTEXT : NO_EXCP);
- enum context ctx = error_context(m);
+ enum context ctx = error_context(m, regs);
struct severity *s;

for (s = severities;; s++) {
@@ -356,7 +358,7 @@ static int mce_severity_intel(struct mce *m, int tolerant, char **msg, bool is_e
}

/* Default to mce_severity_intel */
-int (*mce_severity)(struct mce *m, int tolerant, char **msg, bool is_excp) =
+int (*mce_severity)(struct mce *m, struct pt_regs *regs, int tolerant, char **msg, bool is_excp) =
mce_severity_intel;

void __init mcheck_vendor_init_severity(void)