Don't use the heavy-weight kmap() API to create short-lived mappings
of the scatter-gather list entries that are released as soon as the
entries are written. Instead, use kmap_atomic(), which is more suited
to this purpose.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
drivers/firmware/efi/capsule.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/firmware/efi/capsule.c b/drivers/firmware/efi/capsule.c
index 598b7800d14e..43f6fe7bfe80 100644
--- a/drivers/firmware/efi/capsule.c
+++ b/drivers/firmware/efi/capsule.c
@@ -244,7 +244,7 @@ int efi_capsule_update(efi_capsule_header_t *capsule, phys_addr_t *pages)
for (i = 0; i < sg_count; i++) {
efi_capsule_block_desc_t *sglist;
- sglist = kmap(sg_pages[i]);
+ sglist = kmap_atomic(sg_pages[i]);
for (j = 0; j < SGLIST_PER_PAGE && count > 0; j++) {
u64 sz = min_t(u64, imagesize,
@@ -265,7 +265,7 @@ int efi_capsule_update(efi_capsule_header_t *capsule, phys_addr_t *pages)
else
sglist[j].data = page_to_phys(sg_pages[i + 1]);
- kunmap(sg_pages[i]);
+ kunmap_atomic(sglist);
}
mutex_lock(&capsule_mutex);
--
2.17.1
