[v4,3/5] mtd: rawnand: brcmnand: Fix crash during the panic_write

Message ID 20230706182909.79151-4-william.zhang@broadcom.com
State New
Headers
Series mtd: rawnand: brcmnand: driver and doc updates |

Commit Message

William Zhang July 6, 2023, 6:29 p.m. UTC
  When executing a NAND command within the panic write path, wait for any
pending command instead of calling BUG_ON to avoid crashing while
already crashing.

Fixes: 27c5b17cd1b1 ("mtd: nand: add NAND driver "library" for Broadcom STB NAND controller")
Signed-off-by: William Zhang <william.zhang@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Kursad Oney <kursad.oney@broadcom.com>
Reviewed-by: Kamal Dasu <kamal.dasu@broadcom.com>
Cc: stable@vger.kernel.org

---

Changes in v4:
- Update commit message
- Add cc stable tag

Changes in v3: None
Changes in v2: None

 drivers/mtd/nand/raw/brcmnand/brcmnand.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)
  

Comments

Miquel Raynal July 13, 2023, 7:58 a.m. UTC | #1
On Thu, 2023-07-06 at 18:29:07 UTC, William Zhang wrote:
> When executing a NAND command within the panic write path, wait for any
> pending command instead of calling BUG_ON to avoid crashing while
> already crashing.
> 
> Fixes: 27c5b17cd1b1 ("mtd: nand: add NAND driver "library" for Broadcom STB NAND controller")
> Signed-off-by: William Zhang <william.zhang@broadcom.com>
> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
> Reviewed-by: Kursad Oney <kursad.oney@broadcom.com>
> Reviewed-by: Kamal Dasu <kamal.dasu@broadcom.com>
> Cc: stable@vger.kernel.org

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next, thanks.

Miquel
  

Patch

diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index 9a373a10304d..b2c6396060db 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -1608,7 +1608,17 @@  static void brcmnand_send_cmd(struct brcmnand_host *host, int cmd)
 
 	dev_dbg(ctrl->dev, "send native cmd %d addr 0x%llx\n", cmd, cmd_addr);
 
-	BUG_ON(ctrl->cmd_pending != 0);
+	/*
+	 * If we came here through _panic_write and there is a pending
+	 * command, try to wait for it. If it times out, rather than
+	 * hitting BUG_ON, just return so we don't crash while crashing.
+	 */
+	if (oops_in_progress) {
+		if (ctrl->cmd_pending &&
+			bcmnand_ctrl_poll_status(ctrl, NAND_CTRL_RDY, NAND_CTRL_RDY, 0))
+			return;
+	} else
+		BUG_ON(ctrl->cmd_pending != 0);
 	ctrl->cmd_pending = cmd;
 
 	ret = bcmnand_ctrl_poll_status(ctrl, NAND_CTRL_RDY, NAND_CTRL_RDY, 0);