scsi: qla4xxx: avoid freeing unallocated dma memory

BugLink: https://bugs.launchpad.net/bugs/1837517
[ Upstream commit 608f729c31d4caf52216ea00d20092a80959256d ]

Clang -Wuninitialized notices that on is_qla40XX we never allocate any DMA
memory in get_fw_boot_info() but attempt to free it anyway:

drivers/scsi/qla4xxx/ql4_os.c:5915:7: error: variable 'buf_dma' is used uninitialized whenever 'if' condition is false
      [-Werror,-Wsometimes-uninitialized]
                if (!(val & 0x07)) {
                    ^~~~~~~~~~~~~
drivers/scsi/qla4xxx/ql4_os.c:5985:47: note: uninitialized use occurs here
        dma_free_coherent(&ha->pdev->dev, size, buf, buf_dma);
                                                     ^~~~~~~
drivers/scsi/qla4xxx/ql4_os.c:5915:3: note: remove the 'if' if its condition is always true
                if (!(val & 0x07)) {
                ^~~~~~~~~~~~~~~~~~~
drivers/scsi/qla4xxx/ql4_os.c:5885:20: note: initialize the variable 'buf_dma' to silence this warning
        dma_addr_t buf_dma;
                          ^
                           = 0

Skip the call to dma_free_coherent() here.

Fixes: 2a991c215978 ("[SCSI] qla4xxx: Boot from SAN support for open-iscsi")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index 80289c885c07b3ebe24ba9abb9e8f5088369bd63..9edec8e27b7c15c783dc4cb362a472662216d0e2 100644 (file)
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -5930,7 +5930,7 @@ static int get_fw_boot_info(struct scsi_qla_host *ha, uint16_t ddb_index[])
                val = rd_nvram_byte(ha, sec_addr);
                if (val & BIT_7)
                        ddb_index[1] = (val & 0x7f);
-
+               goto exit_boot_info;
        } else if (is_qla80XX(ha)) {
                buf = dma_alloc_coherent(&ha->pdev->dev, size,
                                         &buf_dma, GFP_KERNEL);