diff mbox series

[net] net: atlantic: fix warning during hot unplug

Message ID 20250202220921.13384-2-mail@jakemoroni.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series [net] net: atlantic: fix warning during hot unplug | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present fail Series targets non-next tree, but doesn't contain any Fixes tags
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 2 this patch: 2
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch warning WARNING: The commit message has 'Call Trace:', perhaps it also needs a 'Fixes:' tag?
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest fail net-next-2025-02-03--09-00 (tests: 930)

Commit Message

Jacob Moroni Feb. 2, 2025, 10:09 p.m. UTC
Firmware deinitialization performs MMIO accesses which are not
necessary if the device has already been removed. In some cases,
these accesses happen via readx_poll_timeout_atomic which ends up
timing out, resulting in a warning at hw_atl2_utils_fw.c:112:

[  104.595913] Call Trace:
[  104.595915]  <TASK>
[  104.595918]  ? show_regs+0x6c/0x80
[  104.595923]  ? __warn+0x8d/0x150
[  104.595925]  ? aq_a2_fw_deinit+0xcf/0xe0 [atlantic]
[  104.595934]  ? report_bug+0x182/0x1b0
[  104.595938]  ? handle_bug+0x6e/0xb0
[  104.595940]  ? exc_invalid_op+0x18/0x80
[  104.595942]  ? asm_exc_invalid_op+0x1b/0x20
[  104.595944]  ? aq_a2_fw_deinit+0xcf/0xe0 [atlantic]
[  104.595952]  ? aq_a2_fw_deinit+0xcf/0xe0 [atlantic]
[  104.595959]  aq_nic_deinit.part.0+0xbd/0xf0 [atlantic]
[  104.595964]  aq_nic_deinit+0x17/0x30 [atlantic]
[  104.595970]  aq_ndev_close+0x2b/0x40 [atlantic]
[  104.595975]  __dev_close_many+0xad/0x160
[  104.595978]  dev_close_many+0x99/0x170
[  104.595979]  unregister_netdevice_many_notify+0x18b/0xb20
[  104.595981]  ? __call_rcu_common+0xcd/0x700
[  104.595984]  unregister_netdevice_queue+0xc6/0x110
[  104.595986]  unregister_netdev+0x1c/0x30
[  104.595988]  aq_pci_remove+0xb1/0xc0 [atlantic]

Fix this by skipping firmware deinitialization altogether if the
PCI device is no longer present.

Tested with an AQC113 attached via Thunderbolt by performing
repeated unplug cycles while traffic was running via iperf.

Signed-off-by: Jacob Moroni <mail@jakemoroni.com>
---
 drivers/net/ethernet/aquantia/atlantic/aq_nic.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

Comments

Igor Russkikh Feb. 3, 2025, 8:55 a.m. UTC | #1
> Firmware deinitialization performs MMIO accesses which are not necessary if the device has already been removed. In some cases, these accesses happen via readx_poll_timeout_atomic which ends up timing out, resulting in a warning at hw_atl2_utils_fw. c: 112: 

Hi Jacob,

Makes sense, thanks!

Reviewed-by: Igor Russkikh <irusskikh@marvell.com>

Igor
Simon Horman Feb. 3, 2025, 10:02 a.m. UTC | #2
On Sun, Feb 02, 2025 at 05:09:21PM -0500, Jacob Moroni wrote:
> Firmware deinitialization performs MMIO accesses which are not
> necessary if the device has already been removed. In some cases,
> these accesses happen via readx_poll_timeout_atomic which ends up
> timing out, resulting in a warning at hw_atl2_utils_fw.c:112:
> 
> [  104.595913] Call Trace:
> [  104.595915]  <TASK>
> [  104.595918]  ? show_regs+0x6c/0x80
> [  104.595923]  ? __warn+0x8d/0x150
> [  104.595925]  ? aq_a2_fw_deinit+0xcf/0xe0 [atlantic]
> [  104.595934]  ? report_bug+0x182/0x1b0
> [  104.595938]  ? handle_bug+0x6e/0xb0
> [  104.595940]  ? exc_invalid_op+0x18/0x80
> [  104.595942]  ? asm_exc_invalid_op+0x1b/0x20
> [  104.595944]  ? aq_a2_fw_deinit+0xcf/0xe0 [atlantic]
> [  104.595952]  ? aq_a2_fw_deinit+0xcf/0xe0 [atlantic]
> [  104.595959]  aq_nic_deinit.part.0+0xbd/0xf0 [atlantic]
> [  104.595964]  aq_nic_deinit+0x17/0x30 [atlantic]
> [  104.595970]  aq_ndev_close+0x2b/0x40 [atlantic]
> [  104.595975]  __dev_close_many+0xad/0x160
> [  104.595978]  dev_close_many+0x99/0x170
> [  104.595979]  unregister_netdevice_many_notify+0x18b/0xb20
> [  104.595981]  ? __call_rcu_common+0xcd/0x700
> [  104.595984]  unregister_netdevice_queue+0xc6/0x110
> [  104.595986]  unregister_netdev+0x1c/0x30
> [  104.595988]  aq_pci_remove+0xb1/0xc0 [atlantic]
> 
> Fix this by skipping firmware deinitialization altogether if the
> PCI device is no longer present.
> 
> Tested with an AQC113 attached via Thunderbolt by performing
> repeated unplug cycles while traffic was running via iperf.
> 

Hi Jacob,

As a fix for net a Fixes tag should go here
(immediately before your signed-off-by line, no blank line in between).

I'm wondering if this one is appropriate: the problem seems
to go all the way back to here.

Fixes: 97bde5c4f909 ("net: ethernet: aquantia: Support for NIC-specific code")

> Signed-off-by: Jacob Moroni <mail@jakemoroni.com>
> ---
>  drivers/net/ethernet/aquantia/atlantic/aq_nic.c | 15 ++++++++-------
>  1 file changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
> index fe0e3e2a8117..e2ae95a01947 100644
> --- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
> +++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
> @@ -1428,7 +1428,7 @@ void aq_nic_deinit(struct aq_nic_s *self, bool link_down)
>  	unsigned int i = 0U;
>  
>  	if (!self)
> -		goto err_exit;
> +		return;
>  
>  	for (i = 0U; i < self->aq_vecs; i++) {
>  		aq_vec = self->aq_vec[i];

This hunk, and the removal of the err_exit label, seem to be more
clean-up than addressing the bug described in the patch description.
I don't think they belong in this patch. But could be candidates for
a follow-up patch targeted at net-next.

> @@ -1441,13 +1441,14 @@ void aq_nic_deinit(struct aq_nic_s *self, bool link_down)
>  	aq_ptp_ring_free(self);
>  	aq_ptp_free(self);
>  
> -	if (likely(self->aq_fw_ops->deinit) && link_down) {
> -		mutex_lock(&self->fwreq_mutex);
> -		self->aq_fw_ops->deinit(self->aq_hw);
> -		mutex_unlock(&self->fwreq_mutex);
> +	/* May be invoked during hot unplug. */
> +	if (pci_device_is_present(self->pdev)) {
> +		if (likely(self->aq_fw_ops->deinit) && link_down) {

Maybe not important, but I would have written this as a single if
condition rather than two.

Also, not really appropriate to change in this patch as it's not part
of the bug, but I'm not sure that likely() is appropriate here:
is this a fast path?

> +			mutex_lock(&self->fwreq_mutex);
> +			self->aq_fw_ops->deinit(self->aq_hw);
> +			mutex_unlock(&self->fwreq_mutex);
> +		}
>  	}
> -
> -err_exit:;
>  }
>  
>  void aq_nic_free_vectors(struct aq_nic_s *self)
Jacob Moroni Feb. 3, 2025, 2:34 p.m. UTC | #3
Hello,

Thanks for the feedback.

> This hunk, and the removal of the err_exit label, seem to be more
> clean-up than addressing the bug described in the patch description.
> I don't think they belong in this patch. But could be candidates for
> a follow-up patch targeted at net-next.

Makes sense. I'll send some follow up patches to clean these up.

Thanks,
Jake
diff mbox series

Patch

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
index fe0e3e2a8117..e2ae95a01947 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
@@ -1428,7 +1428,7 @@  void aq_nic_deinit(struct aq_nic_s *self, bool link_down)
 	unsigned int i = 0U;
 
 	if (!self)
-		goto err_exit;
+		return;
 
 	for (i = 0U; i < self->aq_vecs; i++) {
 		aq_vec = self->aq_vec[i];
@@ -1441,13 +1441,14 @@  void aq_nic_deinit(struct aq_nic_s *self, bool link_down)
 	aq_ptp_ring_free(self);
 	aq_ptp_free(self);
 
-	if (likely(self->aq_fw_ops->deinit) && link_down) {
-		mutex_lock(&self->fwreq_mutex);
-		self->aq_fw_ops->deinit(self->aq_hw);
-		mutex_unlock(&self->fwreq_mutex);
+	/* May be invoked during hot unplug. */
+	if (pci_device_is_present(self->pdev)) {
+		if (likely(self->aq_fw_ops->deinit) && link_down) {
+			mutex_lock(&self->fwreq_mutex);
+			self->aq_fw_ops->deinit(self->aq_hw);
+			mutex_unlock(&self->fwreq_mutex);
+		}
 	}
-
-err_exit:;
 }
 
 void aq_nic_free_vectors(struct aq_nic_s *self)