| Message ID | 1453910247-3447628-6-git-send-email-arnd@arndb.de |
|---|---|
| State | Accepted |
| Commit | 860cd9c07661f767dc2ea1fb2f054fcc02a199c5 |
| Headers | show |
| Series | [1/7] scsi: fdomain: drop fdomain_pci_tbl when built-in | expand |
On 27/01/16 9:27 PM, "Arnd Bergmann" <arnd@arndb.de> wrote: >The qla4_83xx_rd_reg_indirect() function can fail when it is unable >to read a register, but not all callers check its return value before >using the register data, and gcc correctly warns about this: > >qla4xxx/ql4_83xx.c: In function 'qla4_83xx_process_reset_template': >qla4xxx/ql4_83xx.c:1073:36: warning: 'value' may be used uninitialized in >this function > ha->reset_tmplt.array[index++] = value; > ^ >qla4xxx/ql4_83xx.c:1050:11: note: 'value' was declared here > uint32_t value; > ^ >qla4xxx/ql4_83xx.c:902:8: warning: 'value' may be used uninitialized in >this function > value &= p_rmw_hdr->test_mask; > ^ >qla4xxx/ql4_83xx.c:895:11: note: 'value' was declared here > uint32_t value; > ^ >In file included from ../include/linux/io.h:25:0, > from ../include/linux/pci.h:31, > from ../drivers/scsi/qla4xxx/ql4_def.h:16, > from ../drivers/scsi/qla4xxx/ql4_83xx.c:10: >asm/io.h:101:2: warning: 'value' may be used uninitialized in this >function > asm volatile("str %1, %0" > ^ >qla4xxx/ql4_83xx.c:874:11: note: 'value' was declared here > uint32_t value; > ^ > >Unfortunately, I don't see any helpful way to add proper error handling >for this case, and the failure scenario for rd_reg seems rather obscure, >so this bails out and makes the rd_reg accessor set the result to >0xffffffff >so we at least get a predictable value. > >Signed-off-by: Arnd Bergmann <arnd@arndb.de> >--- > drivers/scsi/qla4xxx/ql4_83xx.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > >diff --git a/drivers/scsi/qla4xxx/ql4_83xx.c >b/drivers/scsi/qla4xxx/ql4_83xx.c >index 5d4f8e67fb25..638f72c5ab05 100644 >--- a/drivers/scsi/qla4xxx/ql4_83xx.c >+++ b/drivers/scsi/qla4xxx/ql4_83xx.c >@@ -46,11 +46,13 @@ int qla4_83xx_rd_reg_indirect(struct scsi_qla_host >*ha, uint32_t addr, > > ret_val = qla4_83xx_set_win_base(ha, addr); > >- if (ret_val == QLA_SUCCESS) >+ if (ret_val == QLA_SUCCESS) { > *data = qla4_83xx_rd_reg(ha, QLA83XX_WILDCARD); >- else >+ } else { >+ *data = 0xffffffff; > ql4_printk(KERN_ERR, ha, "%s: failed read of addr 0x%x!\n", > __func__, addr); >+ } > > return ret_val; > } >-- >2.7.0 > Acked-by: Nilesh Javali <nilesh.javali@qlogic.com>
diff --git a/drivers/scsi/qla4xxx/ql4_83xx.c b/drivers/scsi/qla4xxx/ql4_83xx.c index 5d4f8e67fb25..638f72c5ab05 100644 --- a/drivers/scsi/qla4xxx/ql4_83xx.c +++ b/drivers/scsi/qla4xxx/ql4_83xx.c @@ -46,11 +46,13 @@ int qla4_83xx_rd_reg_indirect(struct scsi_qla_host *ha, uint32_t addr, ret_val = qla4_83xx_set_win_base(ha, addr); - if (ret_val == QLA_SUCCESS) + if (ret_val == QLA_SUCCESS) { *data = qla4_83xx_rd_reg(ha, QLA83XX_WILDCARD); - else + } else { + *data = 0xffffffff; ql4_printk(KERN_ERR, ha, "%s: failed read of addr 0x%x!\n", __func__, addr); + } return ret_val; }
The qla4_83xx_rd_reg_indirect() function can fail when it is unable to read a register, but not all callers check its return value before using the register data, and gcc correctly warns about this: qla4xxx/ql4_83xx.c: In function 'qla4_83xx_process_reset_template': qla4xxx/ql4_83xx.c:1073:36: warning: 'value' may be used uninitialized in this function ha->reset_tmplt.array[index++] = value; ^ qla4xxx/ql4_83xx.c:1050:11: note: 'value' was declared here uint32_t value; ^ qla4xxx/ql4_83xx.c:902:8: warning: 'value' may be used uninitialized in this function value &= p_rmw_hdr->test_mask; ^ qla4xxx/ql4_83xx.c:895:11: note: 'value' was declared here uint32_t value; ^ In file included from ../include/linux/io.h:25:0, from ../include/linux/pci.h:31, from ../drivers/scsi/qla4xxx/ql4_def.h:16, from ../drivers/scsi/qla4xxx/ql4_83xx.c:10: asm/io.h:101:2: warning: 'value' may be used uninitialized in this function asm volatile("str %1, %0" ^ qla4xxx/ql4_83xx.c:874:11: note: 'value' was declared here uint32_t value; ^ Unfortunately, I don't see any helpful way to add proper error handling for this case, and the failure scenario for rd_reg seems rather obscure, so this bails out and makes the rd_reg accessor set the result to 0xffffffff so we at least get a predictable value. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/scsi/qla4xxx/ql4_83xx.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) -- 2.7.0