Unwinding loop in error path for this function uses unsigned limit
variable, causing the promotion of the signed counter variable.
--> 204 for (; pfn >= start_pfn; pfn--)
^^^^^^^^^^^^^^^^
If start_pfn can be zero then this is an endless loop. I've seen this
code in other places as well. This loop is slightly off as well. It
should decrement pfn on the first iteration.
Fix by making the loop limit variables signed. Also fix missing
predecrement by modifying to while loop.
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Donald Robson <donald.robson@imgtec.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231208160825.92933-1-donald.robson@imgtec.com
If the call to vmap() fails the "page_nr" is one element beyond the end
of the mips_data->pt_dma_addr[] and mips_data->pt_pages[] arrays.
The way that this is traditionally written is that we clean up the
partial loop iteration before the goto and then we can say
while (--i >= 0). At that point we know that all the elements thus
far are initialized so we don't need to have NULL checks.
Fixes: 927f3e0253 ("drm/imagination: Implement MIPS firmware processor and MMU support")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Frank Binns <frank.binns@imgtec.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/a2d3210b-290f-4397-9c3e-efdcca94d8ac@moroto.mountain
Add support for the MIPS firmware processor, used in the Series AXE GPU.
The MIPS firmware processor uses a separate MMU to the rest of the GPU, so
this patch adds support for that as well.
Changes since v8:
- Corrected license identifiers
Changes since v6:
- Fix integer overflow in VM map error path
Changes since v5:
- Use alloc_page() when allocating MIPS pagetable
Changes since v3:
- Get regs resource (removed from GPU resources commit)
Signed-off-by: Sarah Walker <sarah.walker@imgtec.com>
Signed-off-by: Donald Robson <donald.robson@imgtec.com>
Link: https://lore.kernel.org/r/a114f7b3e97cb07460c7f2842901716a9207b0c4.1700668843.git.donald.robson@imgtec.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
