[PATCH 5.15 087/102] net: atlantic: always deep reset on pm op, fixing up my null deref regression

Greg Kroah-Hartman
2022-05-16T20:07:25Z

From: Manuel Ullmann <labre@posteo.de>

commit 1809c30b6e5a83a1de1435fe01aaa4de4d626a7c upstream.

The impact of this regression is the same for resume that I saw on
thaw: the kernel hangs and nothing except SysRq rebooting can be done.

Fixes regression in commit cbe6c3a8f8f4 ("net: atlantic: invert deep
par in pm functions, preventing null derefs"), where I disabled deep
pm resets in suspend and resume, trying to make sense of the
atl_resume_common() deep parameter in the first place.

It turns out, that atlantic always has to deep reset on pm
operations. Even though I expected that and tested resume, I screwed
up by kexec-rebooting into an unpatched kernel, thus missing the
breakage.

This fixup obsoletes the deep parameter of atl_resume_common, but I
leave the cleanup for the maintainers to post to mainline.

Suspend and hibernation were successfully tested by the reporters.

Fixes: cbe6c3a8f8f4 ("net: atlantic: invert deep par in pm functions, preventing null derefs")
Link: https://lore.kernel.org/regressions/9-Ehc_xXSwdXcvZqKD5aSqsqeNj5Izco4MYEwnx5cySXVEc9-x_WC4C3kAoCqNTi-H38frroUK17iobNVnkLtW36V6VWGSQEOHXhmVMm5iQ=@protonmail.com/
Reported-by: Jordan Leppert <jordanleppert@protonmail.com>
Reported-by: Holger Hoffstaette <holger@applied-asynchrony.com>
Tested-by: Jordan Leppert <jordanleppert@protonmail.com>
Tested-by: Holger Hoffstaette <holger@applied-asynchrony.com>
CC: <stable@vger.kernel.org> # 5.10+
Signed-off-by: Manuel Ullmann <labre@posteo.de>
Link: https://lore.kernel.org/r/87bkw8dfmp.fsf@posteo.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c
@@ -449,7 +449,7 @@ static int aq_pm_freeze(struct device *d

static int aq_pm_suspend_poweroff(struct device *dev)
{
- return aq_suspend_common(dev, false);
+ return aq_suspend_common(dev, true);
}

static int aq_pm_thaw(struct device *dev)
@@ -459,7 +459,7 @@ static int aq_pm_thaw(struct device *dev

static int aq_pm_resume_restore(struct device *dev)
{
- return atl_resume_common(dev, false);
+ return atl_resume_common(dev, true);
}

static const struct dev_pm_ops aq_pm_ops = {