[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH v2] scsi: pvscsi: limit process IO loop to ring size
From: |
P J P |
Subject: |
[Qemu-devel] [PATCH v2] scsi: pvscsi: limit process IO loop to ring size |
Date: |
Wed, 14 Sep 2016 15:09:12 +0530 |
From: Prasad J Pandit <address@hidden>
Vmware Paravirtual SCSI emulator while processing IO requests
could run into an infinite loop if 'pvscsi_ring_pop_req_descr'
always returned positive value. Limit IO loop to the ring size.
Reported-by: Li Qiang <address@hidden>
Signed-off-by: Prasad J Pandit <address@hidden>
---
hw/scsi/vmw_pvscsi.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
Update per:
-> https://lists.gnu.org/archive/html/qemu-devel/2016-09/msg02711.html
diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c
index 4245c15..4d94b36 100644
--- a/hw/scsi/vmw_pvscsi.c
+++ b/hw/scsi/vmw_pvscsi.c
@@ -245,8 +245,11 @@ static hwaddr
pvscsi_ring_pop_req_descr(PVSCSIRingInfo *mgr)
{
uint32_t ready_ptr = RS_GET_FIELD(mgr, reqProdIdx);
+ uint32_t ring_size = PVSCSI_MAX_NUM_PAGES_REQ_RING
+ * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
- if (ready_ptr != mgr->consumed_ptr) {
+ if (ready_ptr != mgr->consumed_ptr
+ && ready_ptr - mgr->consumed_ptr < ring_size) {
uint32_t next_ready_ptr =
mgr->consumed_ptr++ & mgr->txr_len_mask;
uint32_t next_ready_page =
--
2.5.5
- [Qemu-devel] [PATCH v2] scsi: pvscsi: limit process IO loop to ring size,
P J P <=