FAILED: patch "[PATCH] mmc: via-sdmmc: cancel card-detect work on remove" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 57e5d877f898d5e5c9d672a77bb6bdd24f0d9bf5
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026090309-willfully-monorail-6921@gregkh' --subject-prefix 'PATCH 5.15.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 57e5d877f898d5e5c9d672a77bb6bdd24f0d9bf5 Mon Sep 17 00:00:00 2001
From: Fan Wu <[email protected]>
Date: Thu, 23 Jul 2026 11:28:42 +0000
Subject: [PATCH] mmc: via-sdmmc: cancel card-detect work on remove

Disabling the device interrupt and freeing the IRQ prevents new card-detect work from being queued, but carddet_work already queued by the handler can still run after via_sd_remove() returns. via_sdc_card_detect() recovers the host through container_of() and dereferences its MMIO base; once remove() returns the host can be freed, so that work would touch freed memory.

Cancel carddet_work after freeing the IRQ and before cancelling finish_bh_work, which the card-detect handler can also queue. carddet_work can re-enable the interrupt through via_reset_pcictrl(); mask it again afterwards.

This issue was found by an in-house static analysis tool and confirmed by manual code review.

index 632de678532d..4910d0f444ba 100644
@@ -1205,6 +1205,10 @@ static void via_sd_remove(struct pci_dev *pcidev)
 
 	free_irq(pcidev->irq, sdhost);
 
+	cancel_work_sync(&sdhost->carddet_work);
+	/* carddet_work may re-enable the interrupt via via_reset_pcictrl(). */
+	writeb(0x0, sdhost->pcictrl_mmiobase + VIA_CRDR_PCIINTCTRL);
+
 	timer_delete_sync(&sdhost->timer);
 
 	cancel_work_sync(&sdhost->finish_bh_work);

From: Fan Wu <[email protected]>

[ Upstream commit 57e5d877f898d5e5c9d672a77bb6bdd24f0d9bf5 ]

Disabling the device interrupt and freeing the IRQ prevents new card-detect work from being queued, but carddet_work already queued by the handler can still run after via_sd_remove() returns. via_sdc_card_detect() recovers the host through container_of() and dereferences its MMIO base; once remove() returns the host can be freed, so that work would touch freed memory.

Cancel carddet_work after freeing the IRQ and before cancelling finish_bh_work, which the card-detect handler can also queue. carddet_work can re-enable the interrupt through via_reset_pcictrl(); mask it again afterwards.

This issue was found by an in-house static analysis tool and confirmed by manual code review.

---
 drivers/mmc/host/via-sdmmc.c | 4 ++++
 1 file changed, 4 insertions(+)

index a2b0d9461665b..2e367e8d8411c 100644
@@ -1202,6 +1202,10 @@ static void via_sd_remove(struct pci_dev *pcidev)
 
 	free_irq(pcidev->irq, sdhost);
 
+	cancel_work_sync(&sdhost->carddet_work);
+	/* carddet_work may re-enable the interrupt via via_reset_pcictrl(). */
+	writeb(0x0, sdhost->pcictrl_mmiobase + VIA_CRDR_PCIINTCTRL);
+
 	del_timer_sync(&sdhost->timer);
 
 	tasklet_kill(&sdhost->finish_tasklet);

2.53.0