Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Two fixes in this pull request:

   - The writeback regression fix from Tejun, which has been weeks in
     the making.  This fixes a case where we would sometimes not issue
     writeback when we should have.

   - An older fix for a memory corruption issue in mtip32xx.  It was
     deferred since we wanted a better fix for this (driver should not
     have to handle that case), but given the timing, it's better to put
     the simple fix in for 4.2 release"

* 'for-linus' of git://git.kernel.dk/linux-block:
  mtip32x: fix regression introduced by blk-mq per-hctx flush
  writeback: sync_inodes_sb() must write out I_DIRTY_TIME inodes and always call wait_sb_inodes()

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 4a2ef09e6704..f504232c1ee7 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3756,6 +3756,14 @@ static int mtip_init_cmd(void *data, struct request *rq, unsigned int hctx_idx,
 	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
 	u32 host_cap_64 = readl(dd->mmio + HOST_CAP) & HOST_CAP_64;
 
+	/*
+	 * For flush requests, request_idx starts at the end of the
+	 * tag space.  Since we don't support FLUSH/FUA, simply return
+	 * 0 as there's nothing to be done.
+	 */
+	if (request_idx >= MTIP_MAX_COMMAND_SLOTS)
+		return 0;
+
 	cmd->command = dmam_alloc_coherent(&dd->pdev->dev, CMD_DMA_ALLOC_SZ,
 			&cmd->command_dma, GFP_KERNEL);
 	if (!cmd->command)