[PATCH v2] Bluetooth: btintel_pcie: Use blocking reset for FLR

[PATCH v2] Bluetooth: btintel_pcie: Use blocking reset for FLR

[Ravindra]

Several paths request an FLR asynchronously, including S3/S4 resume,
resume recovery, HCI reset, and hardware-error recovery. A queued reset
may run before the PM callback releases the PCI device lock, causing
pci_try_reset_function() to return -EAGAIN without attempting the FLR.

Use pci_reset_function() so reset work waits for the device lock and
performs the FLR once the PM callback releases it. If the reset fails,
clear the recovery in-progress flag so a later reset request can try
again.

Fixes: 9c36951474d8 ("Bluetooth: btintel_pcie: Refactor FLR to use device_reprobe()")
Signed-off-by: Ravindra <ravindra@intel.com>
---
 drivers/bluetooth/btintel_pcie.c | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/bluetooth/btintel_pcie.c b/drivers/bluetooth/btintel_pcie.c
index 3a555aa50c87..92b91f058fce 100644
--- a/drivers/bluetooth/btintel_pcie.c
+++ b/drivers/bluetooth/btintel_pcie.c
@@ -3745,13 +3745,10 @@ static int btintel_pcie_perform_flr(struct btintel_pcie_data *data)
 	struct pci_dev *pdev = data->pdev;
 	int err;
 
-	/* pci_try_reset_function() avoids the device_lock ABBA against
-	 * btintel_pcie_remove(): .remove() runs with device_lock held and
-	 * then waits for this work via disable_work_sync(); the blocking
-	 * pci_reset_function() would deadlock by trying to re-acquire
-	 * device_lock here.
+	/* Reset work runs asynchronously, so it can wait for the device lock
+	 * held by a PM callback to be released.
 	 */
-	err = pci_try_reset_function(pdev);
+	err = pci_reset_function(pdev);
 	if (err) {
 		BT_ERR("Failed resetting the pcie device (%d)", err);
 		return err;
@@ -3817,6 +3814,7 @@ static void btintel_pcie_reset_work(struct work_struct *wk)
 		enable_work(&data->hwexp_work);
 		enable_work(&data->fwtrigger_work);
 		enable_work(&data->mbox_work);
+		clear_bit(BTINTEL_PCIE_RECOVERY_IN_PROGRESS, &data->flags);
 	}
 
 out:
@@ -3841,10 +3839,9 @@ static void btintel_pcie_reset_work(struct work_struct *wk)
  *     in-flight one (whose recovery will reinitialize the device
  *     regardless of the dropped trigger's variant).
  *
- * The bit is cleared only by .remove() / re-probe via fresh devm
- * allocation, which is the intended one-shot semantics: a reset
- * tears down and re-probes 'data', so there is no "in-flight"
- * reset to follow up after device_reprobe() succeeds.
+ * A successful reset clears the bit through .remove() / re-probe via
+ * fresh devm allocation. A failed FLR clears it in reset_work so a
+ * later request can retry; there is no in-flight reset after failure.
  */
 static void btintel_pcie_request_reset(struct btintel_pcie_data *data,
 				       enum btintel_pcie_reset_type type)
-- 
2.43.0

RE: [v2] Bluetooth: btintel_pcie: Use blocking reset for FLR

[bluez.test.bot]

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This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/series/1186224/

---Test result---

Test Summary:
CheckPatch                    PASS      0.92 seconds
VerifyFixes                   PASS      0.06 seconds
VerifySignedoff               PASS      0.06 seconds
GitLint                       PASS      0.21 seconds
SubjectPrefix                 PASS      0.06 seconds
BuildKernel                   PASS      29.56 seconds
CheckAllWarning               PASS      33.43 seconds
CheckSparse                   PASS      36.14 seconds
BuildKernel32                 PASS      32.05 seconds
CheckKernelLLVM               PASS      33.29 seconds
TestRunnerSetup               PASS      716.90 seconds
IncrementalBuild              PASS      28.39 seconds



https://github.com/bluez/bluetooth-next/pull/942

---
Regards,
Linux Bluetooth