[PATCH] net/qla3xxx: Fix a test in ql_reset_work()

Christophe JAILLET posted 1 patch 3 years, 11 months ago
drivers/net/ethernet/qlogic/qla3xxx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
[PATCH] net/qla3xxx: Fix a test in ql_reset_work()
Posted by Christophe JAILLET 3 years, 11 months ago
test_bit() tests if one bit is set or not.
Here the logic seems to check of bit QL_RESET_PER_SCSI (i.e. 4) OR bit
QL_RESET_START (i.e. 3) is set.

In fact, it checks if bit 7 (4 | 3 = 7) is set, that is to say
QL_ADAPTER_UP.

This looks harmless, because this bit is likely be set, and when the
ql_reset_work() delayed work is scheduled in ql3xxx_isr() (the only place
that schedule this work), QL_RESET_START or QL_RESET_PER_SCSI is set.

This has been spotted by smatch.

Fixes: 5a4faa873782 ("[PATCH] qla3xxx NIC driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
This patch is speculative and should certainly be tested by s.o. with the
needed hardware.

Maybe, the whole 'if (test_bit(...)' test should be removed because it is
always true. If it is really the case, this would save 1 level of
indentation.
---
 drivers/net/ethernet/qlogic/qla3xxx.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/qlogic/qla3xxx.c b/drivers/net/ethernet/qlogic/qla3xxx.c
index b30589a135c2..70241faaa841 100644
--- a/drivers/net/ethernet/qlogic/qla3xxx.c
+++ b/drivers/net/ethernet/qlogic/qla3xxx.c
@@ -3614,7 +3614,8 @@ static void ql_reset_work(struct work_struct *work)
 		qdev->mem_map_registers;
 	unsigned long hw_flags;
 
-	if (test_bit((QL_RESET_PER_SCSI | QL_RESET_START), &qdev->flags)) {
+	if (test_bit((QL_RESET_PER_SCSI), &qdev->flags) ||
+	    test_bit((QL_RESET_START), &qdev->flags)) {
 		clear_bit(QL_LINK_MASTER, &qdev->flags);
 
 		/*
-- 
2.34.1
Re: [PATCH] net/qla3xxx: Fix a test in ql_reset_work()
Posted by patchwork-bot+netdevbpf@kernel.org 3 years, 11 months ago
Hello:

This patch was applied to netdev/net.git (master)
by Jakub Kicinski <kuba@kernel.org>:

On Sun, 15 May 2022 20:07:02 +0200 you wrote:
> test_bit() tests if one bit is set or not.
> Here the logic seems to check of bit QL_RESET_PER_SCSI (i.e. 4) OR bit
> QL_RESET_START (i.e. 3) is set.
> 
> In fact, it checks if bit 7 (4 | 3 = 7) is set, that is to say
> QL_ADAPTER_UP.
> 
> [...]

Here is the summary with links:
  - net/qla3xxx: Fix a test in ql_reset_work()
    https://git.kernel.org/netdev/net/c/5361448e45fa

You are awesome, thank you!
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