4.14-stable review patch. If anyone has any objections, please let me know.
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From: William Zhang william.zhang@broadcom.com
commit e66dd317194daae0475fe9e5577c80aa97f16cb9 upstream.
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 Signed-off-by: Miquel Raynal miquel.raynal@bootlin.com Link: https://lore.kernel.org/linux-mtd/20230706182909.79151-4-william.zhang@broad... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/mtd/nand/brcmnand/brcmnand.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
--- a/drivers/mtd/nand/brcmnand/brcmnand.c +++ b/drivers/mtd/nand/brcmnand/brcmnand.c @@ -1271,7 +1271,17 @@ static void brcmnand_send_cmd(struct brc
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);