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authorJames Morse <james.morse@arm.com>2019-01-29 18:48:46 +0000
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2019-02-07 23:10:45 +0100
commit06ddeadc8d1c4f704b8956f239263bca75a3add8 (patch)
treedf503ec06d4753854e25df8dec4fcb702c07a5bc /drivers/acpi/apei
parentee2eb3d4ee175c2fb5c7f67e84f5fe40a8147d92 (diff)
downloadlinux-06ddeadc8d1c4f704b8956f239263bca75a3add8.tar.bz2
ACPI / APEI: Don't allow ghes_ack_error() to mask earlier errors
During ghes_proc() we use ghes_ack_error() to tell an external agent we are done with these records and it can re-use the memory. rc may hold an error returned by ghes_read_estatus(), ENOENT causes us to skip ghes_ack_error() (as there is nothing to ack), but rc may also by EIO, which gets supressed. ghes_clear_estatus() is where we mark the records as processed for non GHESv2 error sources, and already spots the ENOENT case as buf_paddr is set to 0 by ghes_read_estatus(). Move the ghes_ack_error() call in here to avoid extra logic with the return code in ghes_proc(). This enables GHESv2 acking for NMI-like error sources. This is safe as the buffer is pre-mapped by map_gen_v2() before the GHES is added to any NMI handler lists. This same pre-mapping step means we can't receive an error from apei_read()/write() here as apei_check_gar() succeeded when it was mapped, and the mapping was cached, so the address can't be rejected at runtime. Remove the error-returns as this is now called from a function with no return. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/apei')
-rw-r--r--drivers/acpi/apei/ghes.c47
1 files changed, 22 insertions, 25 deletions
diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index babd2d53f319..72c1dac64ea8 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -197,6 +197,21 @@ static void unmap_gen_v2(struct ghes *ghes)
apei_unmap_generic_address(&ghes->generic_v2->read_ack_register);
}
+static void ghes_ack_error(struct acpi_hest_generic_v2 *gv2)
+{
+ int rc;
+ u64 val = 0;
+
+ rc = apei_read(&val, &gv2->read_ack_register);
+ if (rc)
+ return;
+
+ val &= gv2->read_ack_preserve << gv2->read_ack_register.bit_offset;
+ val |= gv2->read_ack_write << gv2->read_ack_register.bit_offset;
+
+ apei_write(val, &gv2->read_ack_register);
+}
+
static struct ghes *ghes_new(struct acpi_hest_generic *generic)
{
struct ghes *ghes;
@@ -361,6 +376,13 @@ static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr)
ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
sizeof(ghes->estatus->block_status), 0);
+
+ /*
+ * GHESv2 type HEST entries introduce support for error acknowledgment,
+ * so only acknowledge the error if this support is present.
+ */
+ if (is_hest_type_generic_v2(ghes))
+ ghes_ack_error(ghes->generic_v2);
}
static void ghes_handle_memory_failure(struct acpi_hest_generic_data *gdata, int sev)
@@ -652,21 +674,6 @@ static void ghes_estatus_cache_add(
rcu_read_unlock();
}
-static int ghes_ack_error(struct acpi_hest_generic_v2 *gv2)
-{
- int rc;
- u64 val = 0;
-
- rc = apei_read(&val, &gv2->read_ack_register);
- if (rc)
- return rc;
-
- val &= gv2->read_ack_preserve << gv2->read_ack_register.bit_offset;
- val |= gv2->read_ack_write << gv2->read_ack_register.bit_offset;
-
- return apei_write(val, &gv2->read_ack_register);
-}
-
static void __ghes_panic(struct ghes *ghes, u64 buf_paddr)
{
__ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus);
@@ -701,16 +708,6 @@ static int ghes_proc(struct ghes *ghes)
out:
ghes_clear_estatus(ghes, buf_paddr);
- if (rc == -ENOENT)
- return rc;
-
- /*
- * GHESv2 type HEST entries introduce support for error acknowledgment,
- * so only acknowledge the error if this support is present.
- */
- if (is_hest_type_generic_v2(ghes))
- return ghes_ack_error(ghes->generic_v2);
-
return rc;
}