This is a note to let you know that I've just added the patch titled
habanalabs: fix mask to obtain page offset
to the 5.13-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:
habanalabs-fix-mask-to-obtain-page-offset.patch
and it can be found in the queue-5.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 008d9259758e5d35d11761f4746a89d720d067d6
Author: Ohad Sharabi <osharabi@xxxxxxxxx>
Date: Thu Jun 3 00:24:32 2021 +0300
habanalabs: fix mask to obtain page offset
[ Upstream commit 0f37510ca34848718db1003479bb4671e8f3c112 ]
When converting virtual address to physical we need to add correct
offset to the physical page.
For this we need to use mask that include ALL bits of page offset.
Signed-off-by: Ohad Sharabi <osharabi@xxxxxxxxx>
Reviewed-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
Signed-off-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/misc/habanalabs/common/mmu/mmu.c b/drivers/misc/habanalabs/common/mmu/mmu.c
index b37189956b14..792d25b79ea6 100644
--- a/drivers/misc/habanalabs/common/mmu/mmu.c
+++ b/drivers/misc/habanalabs/common/mmu/mmu.c
@@ -501,12 +501,20 @@ static void hl_mmu_pa_page_with_offset(struct hl_ctx *ctx, u64 virt_addr,
if ((hops->range_type == HL_VA_RANGE_TYPE_DRAM) &&
!is_power_of_2(prop->dram_page_size)) {
- u32 bit;
+ unsigned long dram_page_size = prop->dram_page_size;
u64 page_offset_mask;
u64 phys_addr_mask;
+ u32 bit;
- bit = __ffs64((u64)prop->dram_page_size);
- page_offset_mask = ((1ull << bit) - 1);
+ /*
+ * find last set bit in page_size to cover all bits of page
+ * offset. note that 1 has to be added to bit index.
+ * note that the internal ulong variable is used to avoid
+ * alignment issue.
+ */
+ bit = find_last_bit(&dram_page_size,
+ sizeof(dram_page_size) * BITS_PER_BYTE) + 1;
+ page_offset_mask = (BIT_ULL(bit) - 1);
phys_addr_mask = ~page_offset_mask;
*phys_addr = (tmp_phys_addr & phys_addr_mask) |
(virt_addr & page_offset_mask);
