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e6599adfad
Previously, vpu->recv_buf and send_buf are forced cast from
void __iomem *tcm. vpu->recv_buf->share_buf is passed to
vpu_ipi_desc.handler(). It's not able to do unaligned access. Otherwise
kernel would crash due to unable to handle kernel paging request.
struct vpu_run {
u32 signaled;
char fw_ver[VPU_FW_VER_LEN];
unsigned int dec_capability;
unsigned int enc_capability;
wait_queue_head_t wq;
};
fw_ver starts at 4 byte boundary. If system enables
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS, strscpy() will do
read_word_at_a_time(), which tries to read 8-byte: *(unsigned long *)addr
vpu_init_ipi_handler() calls strscpy(), which would lead to crash.
vpu_init_ipi_handler() and several other handlers (eg.
vpu_dec_ipi_handler) only do read access to this data, so they can be
const, and we can use memcpy_fromio() to copy the buf to another non iomem
buffer then pass to handler.
Fixes: 85709cbf15 ("media: replace strncpy() by strscpy()")
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.