The NMI-like notifications scribble over ghes->estatus, before
copying it somewhere else. If this interrupts the ghes_probe() code
calling ghes_proc() on each struct ghes, the data is corrupted.
All the NMI-like notifications should use a queued estatus entry
from the beginning, instead of the ghes version, then copying it.
To do this, break up any use of "ghes->estatus" so that all
functions take the estatus as an argument.
This patch just moves these ghes->estatus dereferences into separate
arguments, no change in behaviour. struct ghes becomes unused in
ghes_clear_estatus() as it only wanted ghes->estatus, which we now
pass directly. This is removed.
Signed-off-by: James Morse <james.morse@xxxxxxx>
---
Changes since v6:
* Changed subject
* Renamed ghes_estatus to src_estatus, which is a little clearer
* Removed struct ghes from ghes_clear_estatus() now that this becomes
unused in this patch.
* Mangled the commit message to be different
---
drivers/acpi/apei/ghes.c | 92 +++++++++++++++++++++-------------------
1 file changed, 49 insertions(+), 43 deletions(-)
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index ccad57468ab7..f95db2398dd5 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -293,9 +293,9 @@ static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
}
}
-static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr,
- enum fixed_addresses fixmap_idx)
-
+static int ghes_read_estatus(struct ghes *ghes,
+ struct acpi_hest_generic_status *estatus,
+ u64 *buf_paddr, enum fixed_addresses fixmap_idx)
{
struct acpi_hest_generic *g = ghes->generic;
u32 len;
@@ -312,25 +312,25 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr,
if (!*buf_paddr)
return -ENOENT;
- ghes_copy_tofrom_phys(ghes->estatus, *buf_paddr,
- sizeof(*ghes->estatus), 1, fixmap_idx);
- if (!ghes->estatus->block_status) {
+ ghes_copy_tofrom_phys(estatus, *buf_paddr, sizeof(*estatus), 1,
+ fixmap_idx);
+ if (!estatus->block_status) {
*buf_paddr = 0;
return -ENOENT;
}
rc = -EIO;
- len = cper_estatus_len(ghes->estatus);
- if (len < sizeof(*ghes->estatus))
+ len = cper_estatus_len(estatus);
+ if (len < sizeof(*estatus))
goto err_read_block;
if (len > ghes->generic->error_block_length)
goto err_read_block;
- if (cper_estatus_check_header(ghes->estatus))
+ if (cper_estatus_check_header(estatus))
goto err_read_block;
- ghes_copy_tofrom_phys(ghes->estatus + 1,
- *buf_paddr + sizeof(*ghes->estatus),
- len - sizeof(*ghes->estatus), 1, fixmap_idx);
- if (cper_estatus_check(ghes->estatus))
+ ghes_copy_tofrom_phys(estatus + 1,
+ *buf_paddr + sizeof(*estatus),
+ len - sizeof(*estatus), 1, fixmap_idx);
+ if (cper_estatus_check(estatus))
goto err_read_block;
rc = 0;
@@ -342,16 +342,17 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr,
return rc;
}
-static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr,
- enum fixed_addresses fixmap_idx)
+static void ghes_clear_estatus(struct ghes *ghes,
+ struct acpi_hest_generic_status *estatus,
+ u64 buf_paddr, enum fixed_addresses fixmap_idx)
{
- ghes->estatus->block_status = 0;
+ estatus->block_status = 0;
if (!buf_paddr)
return;
- ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
- sizeof(ghes->estatus->block_status), 0,
+ ghes_copy_tofrom_phys(estatus, buf_paddr,
+ sizeof(estatus->block_status), 0,
fixmap_idx);
/*
@@ -651,12 +652,13 @@ static void ghes_estatus_cache_add(
rcu_read_unlock();
}
-static void __ghes_panic(struct ghes *ghes, u64 buf_paddr,
- enum fixed_addresses fixmap_idx)
+static void __ghes_panic(struct ghes *ghes,
+ struct acpi_hest_generic_status *estatus,
+ u64 buf_paddr, enum fixed_addresses fixmap_idx)
{
- __ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus);
+ __ghes_print_estatus(KERN_EMERG, ghes->generic, estatus);
- ghes_clear_estatus(ghes, buf_paddr, fixmap_idx);
+ ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
/* reboot to log the error! */
if (!panic_timeout)
@@ -666,25 +668,25 @@ static void __ghes_panic(struct ghes *ghes, u64 buf_paddr,
static int ghes_proc(struct ghes *ghes)
{
+ struct acpi_hest_generic_status *estatus = ghes->estatus;
u64 buf_paddr;
int rc;
- rc = ghes_read_estatus(ghes, &buf_paddr, FIX_APEI_GHES_IRQ);
+ rc = ghes_read_estatus(ghes, estatus, &buf_paddr, FIX_APEI_GHES_IRQ);
if (rc)
goto out;
- if (ghes_severity(ghes->estatus->error_severity) >= GHES_SEV_PANIC) {
- __ghes_panic(ghes, buf_paddr, FIX_APEI_GHES_IRQ);
- }
+ if (ghes_severity(estatus->error_severity) >= GHES_SEV_PANIC)
+ __ghes_panic(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ);
- if (!ghes_estatus_cached(ghes->estatus)) {
- if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus))
- ghes_estatus_cache_add(ghes->generic, ghes->estatus);
+ if (!ghes_estatus_cached(estatus)) {
+ if (ghes_print_estatus(NULL, ghes->generic, estatus))
+ ghes_estatus_cache_add(ghes->generic, estatus);
}
- ghes_do_proc(ghes, ghes->estatus);
+ ghes_do_proc(ghes, estatus);
out:
- ghes_clear_estatus(ghes, buf_paddr, FIX_APEI_GHES_IRQ);
+ ghes_clear_estatus(ghes, estatus, buf_paddr, FIX_APEI_GHES_IRQ);
return rc;
}
@@ -825,17 +827,20 @@ static void ghes_print_queued_estatus(void)
}
/* Save estatus for further processing in IRQ context */
-static void __process_error(struct ghes *ghes)
+static void __process_error(struct ghes *ghes,
+ struct acpi_hest_generic_status *src_estatus)
{
-#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
u32 len, node_len;
struct ghes_estatus_node *estatus_node;
struct acpi_hest_generic_status *estatus;
- if (ghes_estatus_cached(ghes->estatus))
+ if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG))
return;
- len = cper_estatus_len(ghes->estatus);
+ if (ghes_estatus_cached(src_estatus))
+ return;
+
+ len = cper_estatus_len(src_estatus);
node_len = GHES_ESTATUS_NODE_LEN(len);
estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len);
@@ -845,30 +850,31 @@ static void __process_error(struct ghes *ghes)
estatus_node->ghes = ghes;
estatus_node->generic = ghes->generic;
estatus = GHES_ESTATUS_FROM_NODE(estatus_node);
- memcpy(estatus, ghes->estatus, len);
+ memcpy(estatus, src_estatus, len);
llist_add(&estatus_node->llnode, &ghes_estatus_llist);
-#endif
}
static int ghes_in_nmi_queue_one_entry(struct ghes *ghes,
enum fixed_addresses fixmap_idx)
{
+ struct acpi_hest_generic_status *estatus = ghes->estatus;
u64 buf_paddr;
int sev;
- if (ghes_read_estatus(ghes, &buf_paddr, fixmap_idx)) {
- ghes_clear_estatus(ghes, buf_paddr, fixmap_idx);
+ if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) {
+ ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
return -ENOENT;
}
- sev = ghes_severity(ghes->estatus->error_severity);
+ sev = ghes_severity(estatus->error_severity);
if (sev >= GHES_SEV_PANIC) {
ghes_print_queued_estatus();
- __ghes_panic(ghes, buf_paddr, fixmap_idx);
+ __ghes_panic(ghes, estatus, buf_paddr, fixmap_idx);
+
}
- __process_error(ghes);
- ghes_clear_estatus(ghes, buf_paddr, fixmap_idx);
+ __process_error(ghes, estatus);
+ ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx);
return 0;
}
--
2.20.1
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