From 4dfdaf4d92241d70103d829fbd04937c83c727b1 Mon Sep 17 00:00:00 2001 From: Andriy Gapon Date: Tue, 8 Sep 2020 05:46:10 +0000 Subject: [PATCH] mmc_da: make sure that part_index is not used uninitialized in sddastart This is a fix to r334065. Without this change I once got stuck I/O with endless partition switching: (sdda0:aw_mmc_sim2:0:0:0): sddastart (sdda0:aw_mmc_sim2:0:0:0): Partition 0 -> -525703168 (sdda0:aw_mmc_sim2:0:0:0): xpt_action: func 0x91d XPT_MMC_IO (sdda0:aw_mmc_sim2:0:0:0): xpt_done: func= 0x91d XPT_MMC_IO status 0x1 (sdda0:aw_mmc_sim2:0:0:0): sddadone (sdda0:aw_mmc_sim2:0:0:0): Card status: 00000000 (sdda0:aw_mmc_sim2:0:0:0): Current state: 4 (sdda0:aw_mmc_sim2:0:0:0): Compteting partition switch to 0 Note that -525703168 (an int) is 0xe0aa6800 in binary representation. The partition indexes are actually stored as uint8_t, so that value was converted / truncated to zero. MFC after: 1 week --- sys/cam/mmc/mmc_da.c | 1 + 1 file changed, 1 insertion(+) diff --git a/sys/cam/mmc/mmc_da.c b/sys/cam/mmc/mmc_da.c index 6bec3b11b9b..d95f185a67a 100644 --- a/sys/cam/mmc/mmc_da.c +++ b/sys/cam/mmc/mmc_da.c @@ -1808,6 +1808,7 @@ sddastart(struct cam_periph *periph, union ccb *start_ccb) } /* Find partition that has outstanding commands. Prefer current partition. */ + part_index = softc->part_curr; part = softc->part[softc->part_curr]; bp = bioq_first(&part->bio_queue); if (bp == NULL) {