[PATCH 5.4 65/72] s390/zcrypt: fix kmalloc 256k failure

From: Greg Kroah-Hartman
Date: Mon Sep 21 2020 - 12:50:23 EST


From: Harald Freudenberger <freude@xxxxxxxxxxxxx>

commit b6186d7fb53349efd274263a45f0b08749ccaa2d upstream.

Tests showed that under stress conditions the kernel may
temporary fail to allocate 256k with kmalloc. However,
this fix reworks the related code in the cca_findcard2()
function to use kvmalloc instead.

Signed-off-by: Harald Freudenberger <freude@xxxxxxxxxxxxx>
Reviewed-by: Ingo Franzki <ifranzki@xxxxxxxxxxxxx>
Cc: Stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/s390/crypto/zcrypt_ccamisc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/s390/crypto/zcrypt_ccamisc.c
+++ b/drivers/s390/crypto/zcrypt_ccamisc.c
@@ -1684,9 +1684,9 @@ int cca_findcard2(u32 **apqns, u32 *nr_a
*nr_apqns = 0;

/* fetch status of all crypto cards */
- device_status = kmalloc_array(MAX_ZDEV_ENTRIES_EXT,
- sizeof(struct zcrypt_device_status_ext),
- GFP_KERNEL);
+ device_status = kvmalloc_array(MAX_ZDEV_ENTRIES_EXT,
+ sizeof(struct zcrypt_device_status_ext),
+ GFP_KERNEL);
if (!device_status)
return -ENOMEM;
zcrypt_device_status_mask_ext(device_status);
@@ -1754,7 +1754,7 @@ int cca_findcard2(u32 **apqns, u32 *nr_a
verify = 0;
}

- kfree(device_status);
+ kvfree(device_status);
return rc;
}
EXPORT_SYMBOL(cca_findcard2);