Commit a05829a7222e ("cfg80211: avoid holding the RTNL when calling the
driver") replaced the rtnl_lock parameter passed to various brcmf
functions with just lock, because since that commit it is not just
about the rtnl_lock but also about the wiphy_lock .
During this search/replace the "if (!rtnl_locked)" check in brcmfmac/p2p.c
was accidentally replaced with "if (locked)", dropping the inversion of
the check. This causes the code to now call rtnl_lock() while already
holding the lock, causing a deadlock.
Add back the "!" to the if-condition to fix this.
Cc: Johannes Berg <[email protected]>
Fixes: a05829a7222e ("cfg80211: avoid holding the RTNL when calling the driver")
Signed-off-by: Hans de Goede <[email protected]>
---
drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
index 6d30a0fcecea..34cd8a7401fe 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
@@ -2439,7 +2439,7 @@ void brcmf_p2p_ifp_removed(struct brcmf_if *ifp, bool locked)
vif = ifp->vif;
cfg = wdev_to_cfg(&vif->wdev);
cfg->p2p.bss_idx[P2PAPI_BSSCFG_DEVICE].vif = NULL;
- if (locked) {
+ if (!locked) {
rtnl_lock();
wiphy_lock(cfg->wiphy);
cfg80211_unregister_wdev(&vif->wdev);
--
2.30.2
On Sat, 2021-03-13 at 15:36 +0100, Hans de Goede wrote:
> Commit a05829a7222e ("cfg80211: avoid holding the RTNL when calling the
> driver") replaced the rtnl_lock parameter passed to various brcmf
> functions with just lock, because since that commit it is not just
> about the rtnl_lock but also about the wiphy_lock .
>
> During this search/replace the "if (!rtnl_locked)" check in brcmfmac/p2p.c
> was accidentally replaced with "if (locked)", dropping the inversion of
> the check. This causes the code to now call rtnl_lock() while already
> holding the lock, causing a deadlock.
>
> Add back the "!" to the if-condition to fix this.
Ouch, sorry about that, and thanks for the fix!
johannes
Hans de Goede <[email protected]> wrote:
> Commit a05829a7222e ("cfg80211: avoid holding the RTNL when calling the
> driver") replaced the rtnl_lock parameter passed to various brcmf
> functions with just lock, because since that commit it is not just
> about the rtnl_lock but also about the wiphy_lock .
>
> During this search/replace the "if (!rtnl_locked)" check in brcmfmac/p2p.c
> was accidentally replaced with "if (locked)", dropping the inversion of
> the check. This causes the code to now call rtnl_lock() while already
> holding the lock, causing a deadlock.
>
> Add back the "!" to the if-condition to fix this.
>
> Cc: Johannes Berg <[email protected]>
> Fixes: a05829a7222e ("cfg80211: avoid holding the RTNL when calling the driver")
> Signed-off-by: Hans de Goede <[email protected]>
Patch applied to wireless-drivers.git, thanks.
bd83a2fc05ed brcmfmac: p2p: Fix recently introduced deadlock issue
--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches