This is a note to let you know that I've just added the patch titled
RDMA: Handle the return code from dma_resv_wait_timeout() properly
to the 5.19-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:
rdma-handle-the-return-code-from-dma_resv_wait_timeout-properly.patch
and it can be found in the queue-5.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From b16de8b9e7d1aae169d059c3a0dd9a881a3c0d1d Mon Sep 17 00:00:00 2001
From: Jason Gunthorpe <jgg@xxxxxxxxxx>
Date: Tue, 16 Aug 2022 11:03:20 -0300
Subject: RDMA: Handle the return code from dma_resv_wait_timeout() properly
From: Jason Gunthorpe <jgg@xxxxxxxxxx>
commit b16de8b9e7d1aae169d059c3a0dd9a881a3c0d1d upstream.
ib_umem_dmabuf_map_pages() returns 0 on success and -ERRNO on failure.
dma_resv_wait_timeout() uses a different scheme:
* Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or
* greater than zero on success.
This results in ib_umem_dmabuf_map_pages() being non-functional as a
positive return will be understood to be an error by drivers.
Fixes: f30bceab16d1 ("RDMA: use dma_resv_wait() instead of extracting the fence")
Cc: stable@xxxxxxxxxx
Link: https://lore.kernel.org/r/0-v1-d8f4e1fa84c8+17-rdma_dmabuf_fix_jgg@xxxxxxxxxx
Tested-by: Maor Gottlieb <maorg@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/core/umem_dmabuf.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/infiniband/core/umem_dmabuf.c b/drivers/infiniband/core/umem_dmabuf.c
index fce80a4a5147..04c04e6d24c3 100644
--- a/drivers/infiniband/core/umem_dmabuf.c
+++ b/drivers/infiniband/core/umem_dmabuf.c
@@ -18,6 +18,7 @@ int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
struct scatterlist *sg;
unsigned long start, end, cur = 0;
unsigned int nmap = 0;
+ long ret;
int i;
dma_resv_assert_held(umem_dmabuf->attach->dmabuf->resv);
@@ -67,9 +68,14 @@ int ib_umem_dmabuf_map_pages(struct ib_umem_dmabuf *umem_dmabuf)
* may be not up-to-date. Wait for the exporter to finish
* the migration.
*/
- return dma_resv_wait_timeout(umem_dmabuf->attach->dmabuf->resv,
+ ret = dma_resv_wait_timeout(umem_dmabuf->attach->dmabuf->resv,
DMA_RESV_USAGE_KERNEL,
false, MAX_SCHEDULE_TIMEOUT);
+ if (ret < 0)
+ return ret;
+ if (ret == 0)
+ return -ETIMEDOUT;
+ return 0;
}
EXPORT_SYMBOL(ib_umem_dmabuf_map_pages);
--
2.37.2
Patches currently in stable-queue which might be from jgg@xxxxxxxxxx are
queue-5.19/rdma-handle-the-return-code-from-dma_resv_wait_timeout-properly.patch
