Subject: FAILED: patch "[PATCH] mmc: via-sdmmc: cancel card-detect work on remove" failed to apply to 6.6-stable tree
To: fanwu01@zju.edu.cn,ulfh@kernel.org
Cc: <stable@vger.kernel.org>
From: <gregkh@linuxfoundation.org>
Date: Thu, 03 Sep 2026 16:47:08 +0200
Message-ID: <2026090308-drainage-dandruff-6985@gregkh>
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The patch below does not apply to the 6.6-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 <stable@vger.kernel.org>.

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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 57e5d877f898d5e5c9d672a77bb6bdd24f0d9bf5
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026090308-drainage-dandruff-6985@gregkh' --subject-prefix 'PATCH 6.6.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 <fanwu01@zju.edu.cn>
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.

Fixes: f0bf7f61b840 ("mmc: Add new via-sdmmc host controller driver")
Cc: stable@vger.kernel.org
Assisted-by: Codex:gpt-5.6
Signed-off-by: Fan Wu <fanwu01@zju.edu.cn>
Signed-off-by: Ulf Hansson <ulfh@kernel.org>

diff --git a/drivers/mmc/host/via-sdmmc.c b/drivers/mmc/host/via-sdmmc.c
index 632de678532d..4910d0f444ba 100644
--- a/drivers/mmc/host/via-sdmmc.c
+++ b/drivers/mmc/host/via-sdmmc.c
@@ -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);