diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2016-09-16 00:36:58 +0200 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-11-28 15:11:17 +0100 |
commit | 75f19f8c3006970632303b49043b075dc4fe922e (patch) | |
tree | f71c491df99f2e8bc7fec88b839d603cce027180 /hw | |
parent | 00227fefd2059464cd2f59aed29944874c630e2f (diff) |
megasas: do not call pci_dma_unmap after having freed the frame once
Commit 8cc4678 ("megasas: remove useless check for cmd->frame", 2016-07-17) was
wrong because I trusted Coverity too much. It turns out that there _is_ a
path through which cmd->frame can become NULL. After megasas_handle_frame's
switch (md->frame->header.frame_cmd), megasas_init_firmware can be called.
From there, megasas_reset_frames will call megasas_unmap_frame which resets
cmd->frame = NULL.
However, there is another bug to fix in there, because megasas_unmap_frame
is called again after setting the command status. In this case QEMU should
not do anything, instead it calls pci_dma_unmap again. Harmless, but
better fix it.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'hw')
-rw-r--r-- | hw/scsi/megasas.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c index 52a41239cf..ca62952941 100644 --- a/hw/scsi/megasas.c +++ b/hw/scsi/megasas.c @@ -461,9 +461,12 @@ static void megasas_unmap_frame(MegasasState *s, MegasasCmd *cmd) { PCIDevice *p = PCI_DEVICE(s); - pci_dma_unmap(p, cmd->frame, cmd->pa_size, 0, 0); + if (cmd->pa_size) { + pci_dma_unmap(p, cmd->frame, cmd->pa_size, 0, 0); + } cmd->frame = NULL; cmd->pa = 0; + cmd->pa_size = 0; clear_bit(cmd->index, s->frame_map); } |