From: Vincent Mailhol mailhol.vincent@wanadoo.fr
stable inclusion from stable-v5.10.137 commit a7a7488cb15a8ff3af6185907a44ac7c8d8c50c1 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 9950f11211331180269867aef848c7cf56861742 ]
After commit 3a5c7e4611dd, the variable errc is accessed before being initialized, c.f. below W=2 warning:
| In function 'pch_can_error', | inlined from 'pch_can_poll' at drivers/net/can/pch_can.c:739:4: | drivers/net/can/pch_can.c:501:29: warning: 'errc' may be used uninitialized [-Wmaybe-uninitialized] | 501 | cf->data[6] = errc & PCH_TEC; | | ^ | drivers/net/can/pch_can.c: In function 'pch_can_poll': | drivers/net/can/pch_can.c:484:13: note: 'errc' was declared here | 484 | u32 errc, lec; | | ^~~~
Moving errc initialization up solves this issue.
Fixes: 3a5c7e4611dd ("can: pch_can: do not report txerr and rxerr during bus-off") Reported-by: Nathan Chancellor nathan@kernel.org Signed-off-by: Vincent Mailhol mailhol.vincent@wanadoo.fr Reviewed-by: Nathan Chancellor nathan@kernel.org Link: https://lore.kernel.org/all/20220721160032.9348-1-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Wei Li liwei391@huawei.com --- drivers/net/can/pch_can.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c index 1adfcc0b9424..1272ec793a8d 100644 --- a/drivers/net/can/pch_can.c +++ b/drivers/net/can/pch_can.c @@ -489,6 +489,7 @@ static void pch_can_error(struct net_device *ndev, u32 status) if (!skb) return;
+ errc = ioread32(&priv->regs->errc); if (status & PCH_BUS_OFF) { pch_can_set_tx_all(priv, 0); pch_can_set_rx_all(priv, 0); @@ -501,7 +502,6 @@ static void pch_can_error(struct net_device *ndev, u32 status) cf->data[7] = (errc & PCH_REC) >> 8; }
- errc = ioread32(&priv->regs->errc); /* Warning interrupt. */ if (status & PCH_EWARN) { state = CAN_STATE_ERROR_WARNING;