This is a note to let you know that I've just added the patch titled 3w-xxxx: fix command completion race to the 4.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: 3w-xxxx-fix-command-completion-race.patch and it can be found in the queue-4.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 9cd9554615cba14f0877cc9972a6537ad2bdde61 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig <hch@xxxxxx> Date: Thu, 23 Apr 2015 09:48:50 +0200 Subject: 3w-xxxx: fix command completion race From: Christoph Hellwig <hch@xxxxxx> commit 9cd9554615cba14f0877cc9972a6537ad2bdde61 upstream. The 3w-xxxx driver needs to tear down the dma mappings before returning the command to the midlayer, as there is no guarantee the sglist and count are valid after that point. Also remove the dma mapping helpers which have another inherent race due to the request_id index. Signed-off-by: Christoph Hellwig <hch@xxxxxx> Acked-by: Adam Radford <aradford@xxxxxxxxx> Signed-off-by: James Bottomley <JBottomley@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/3w-xxxx.c | 42 ++++++------------------------------------ drivers/scsi/3w-xxxx.h | 5 ----- 2 files changed, 6 insertions(+), 41 deletions(-) --- a/drivers/scsi/3w-xxxx.c +++ b/drivers/scsi/3w-xxxx.c @@ -1271,32 +1271,6 @@ static int tw_initialize_device_extensio return 0; } /* End tw_initialize_device_extension() */ -static int tw_map_scsi_sg_data(struct pci_dev *pdev, struct scsi_cmnd *cmd) -{ - int use_sg; - - dprintk(KERN_WARNING "3w-xxxx: tw_map_scsi_sg_data()\n"); - - use_sg = scsi_dma_map(cmd); - if (use_sg < 0) { - printk(KERN_WARNING "3w-xxxx: tw_map_scsi_sg_data(): pci_map_sg() failed.\n"); - return 0; - } - - cmd->SCp.phase = TW_PHASE_SGLIST; - cmd->SCp.have_data_in = use_sg; - - return use_sg; -} /* End tw_map_scsi_sg_data() */ - -static void tw_unmap_scsi_data(struct pci_dev *pdev, struct scsi_cmnd *cmd) -{ - dprintk(KERN_WARNING "3w-xxxx: tw_unmap_scsi_data()\n"); - - if (cmd->SCp.phase == TW_PHASE_SGLIST) - scsi_dma_unmap(cmd); -} /* End tw_unmap_scsi_data() */ - /* This function will reset a device extension */ static int tw_reset_device_extension(TW_Device_Extension *tw_dev) { @@ -1319,8 +1293,8 @@ static int tw_reset_device_extension(TW_ srb = tw_dev->srb[i]; if (srb != NULL) { srb->result = (DID_RESET << 16); - tw_dev->srb[i]->scsi_done(tw_dev->srb[i]); - tw_unmap_scsi_data(tw_dev->tw_pci_dev, tw_dev->srb[i]); + scsi_dma_unmap(srb); + srb->scsi_done(srb); } } } @@ -1767,8 +1741,8 @@ static int tw_scsiop_read_write(TW_Devic command_packet->byte8.io.lba = lba; command_packet->byte6.block_count = num_sectors; - use_sg = tw_map_scsi_sg_data(tw_dev->tw_pci_dev, tw_dev->srb[request_id]); - if (!use_sg) + use_sg = scsi_dma_map(srb); + if (use_sg <= 0) return 1; scsi_for_each_sg(tw_dev->srb[request_id], sg, use_sg, i) { @@ -1955,9 +1929,6 @@ static int tw_scsi_queue_lck(struct scsi /* Save the scsi command for use by the ISR */ tw_dev->srb[request_id] = SCpnt; - /* Initialize phase to zero */ - SCpnt->SCp.phase = TW_PHASE_INITIAL; - switch (*command) { case READ_10: case READ_6: @@ -2185,12 +2156,11 @@ static irqreturn_t tw_interrupt(int irq, /* Now complete the io */ if ((error != TW_ISR_DONT_COMPLETE)) { + scsi_dma_unmap(tw_dev->srb[request_id]); + tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]); tw_dev->state[request_id] = TW_S_COMPLETED; tw_state_request_finish(tw_dev, request_id); tw_dev->posted_request_count--; - tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]); - - tw_unmap_scsi_data(tw_dev->tw_pci_dev, tw_dev->srb[request_id]); } } --- a/drivers/scsi/3w-xxxx.h +++ b/drivers/scsi/3w-xxxx.h @@ -195,11 +195,6 @@ static unsigned char tw_sense_table[][4] #define TW_AEN_SMART_FAIL 0x000F #define TW_AEN_SBUF_FAIL 0x0024 -/* Phase defines */ -#define TW_PHASE_INITIAL 0 -#define TW_PHASE_SINGLE 1 -#define TW_PHASE_SGLIST 2 - /* Misc defines */ #define TW_ALIGNMENT_6000 64 /* 64 bytes */ #define TW_ALIGNMENT_7000 4 /* 4 bytes */ Patches currently in stable-queue which might be from hch@xxxxxx are queue-4.0/3w-9xxx-fix-command-completion-race.patch queue-4.0/scsi-add-1024-max-sectors-black-list-flag.patch queue-4.0/3w-xxxx-fix-command-completion-race.patch queue-4.0/3w-sas-fix-command-completion-race.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html