drm/radeon/si: make sure mc ucode is loaded before checking the size

commit 8c79bae6a30f606b7a4e17c994bc5f72f8fdaf11 upstream.

Avoid a possible segfault.

Noticed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index de0c2bfcc7fc8300d1e75d39f56acaa78a7c795c..bbd83f5aa75dccf44cf1cfb6520a78ac1a7010f0 100644 (file)
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -1475,11 +1475,13 @@ static int si_mc_load_microcode(struct radeon_device *rdev)
        const __be32 *fw_data;
        u32 running, blackout = 0;
        u32 *io_mc_regs;
-       int i, regs_size, ucode_size = rdev->mc_fw->size / 4;
+       int i, regs_size, ucode_size;
 
        if (!rdev->mc_fw)
                return -EINVAL;
 
+       ucode_size = rdev->mc_fw->size / 4;
+
        switch (rdev->family) {
        case CHIP_TAHITI:
                io_mc_regs = (u32 *)&tahiti_io_mc_regs;