Patch "drm/amdkfd: Fix SDMA ring buffer size calculation" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

drm/amdkfd: Fix SDMA ring buffer size calculation

to the 4.4-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:
drm-amdkfd-fix-sdma-ring-buffer-size-calculation.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: shaoyunl <[email protected]>
Date: Wed, 1 Nov 2017 19:21:56 -0400
Subject: drm/amdkfd: Fix SDMA ring buffer size calculation

From: shaoyunl <[email protected]>

[ Upstream commit d12fb13f23199faa7e536acec1db49068e5a067d ]

ffs function return the position of the first bit set on 1 based. (bit zero returns 1).

---
 drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_cik.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -215,8 +215,8 @@ static int update_mqd_sdma(struct mqd_ma
 	BUG_ON(!mm || !mqd || !q);
 
 	m = get_sdma_mqd(mqd);
-	m->sdma_rlc_rb_cntl = ffs(q->queue_size / sizeof(unsigned int)) <<
-			SDMA0_RLC0_RB_CNTL__RB_SIZE__SHIFT |
+	m->sdma_rlc_rb_cntl = (ffs(q->queue_size / sizeof(unsigned int)) - 1)
+			<< SDMA0_RLC0_RB_CNTL__RB_SIZE__SHIFT |
 			q->vmid << SDMA0_RLC0_RB_CNTL__RB_VMID__SHIFT |
 			1 << SDMA0_RLC0_RB_CNTL__RPTR_WRITEBACK_ENABLE__SHIFT |
 			6 << SDMA0_RLC0_RB_CNTL__RPTR_WRITEBACK_TIMER__SHIFT;

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/drm-amdkfd-fix-sdma-ring-buffer-size-calculation.patch