The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function
returns the number of the created entries in the DMA address space.
However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and
dma_unmap_sg must be called with the original number of the entries
passed to the dma_map_sg().
struct sg_table is a common structure used for describing a non-contiguous
memory buffer, used commonly in the DRM and graphics subsystems. It
consists of a scatterlist with memory pages and DMA addresses (sgl entry),
as well as the number of scatterlist entries: CPU pages (orig_nents entry)
and DMA mapped pages (nents entry).
It turned out that it was a common mistake to misuse nents and orig_nents
entries, calling DMA-mapping functions with a wrong number of entries or
ignoring the number of mapped entries returned by the dma_map_sg()
function.
To avoid such issues, lets use a common dma-mapping wrappers operating
directly on the struct sg_table objects and use scatterlist page
iterators where possible. This, almost always, hides references to the
nents and orig_nents entries, making the code robust, easier to follow
and copy/paste safe.
While touching this code, also add missing call to dma_unmap_sgtable.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:
- not detecting pgoff<<PAGE_SHIFT overflow
- not detecting (pgoff<<PAGE_SHIFT)+usize overflow
- not checking whether addr and addr+(pgoff<<PAGE_SHIFT) are the same
vmalloc allocation
- comparing a potentially wildly out-of-bounds pointer with the end of
the vmalloc region
In particular, since commit fc9702273e ("bpf: Add mmap() support for
BPF_MAP_TYPE_ARRAY"), unprivileged users can cause kernel null pointer
dereferences by calling mmap() on a BPF map with a size that is bigger
than the distance from the start of the BPF map to the end of the
address space.
This could theoretically be used as a kernel ASLR bypass, by using
whether mmap() with a given offset oopses or returns an error code to
perform a binary search over the possible address range.
To allow remap_vmalloc_range_partial() to verify that addr and
addr+(pgoff<<PAGE_SHIFT) are in the same vmalloc region, pass the offset
to remap_vmalloc_range_partial() instead of adding it to the pointer in
remap_vmalloc_range().
In remap_vmalloc_range_partial(), fix the check against
get_vm_area_size() by using size comparisons instead of pointer
comparisons, and add checks for pgoff.
Fixes: 833423143c ("[PATCH] mm: introduce remap_vmalloc_range()")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While generating interrupt, mdev_state is already available for which
interrupt is generated.
Instead of doing indirect way from state->device->uuid-> to searching
state linearly in linked list on every interrupt generation,
directly use the available state.
Hence, simplify the code to use mdev_state and remove unused helper
function with that.
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The "WITH Linux-syscall-note" exception exists for headers exported to
user space. It is strange to add it to non-exported headers.
Commit 687a3e4d8e ("treewide: remove SPDX "WITH Linux-syscall-note"
from kernel-space headers") did cleanups some months ago, but it looks
like we need to do this periodically.
This patch was generated by the following script:
git grep -l -e Linux-syscall-note \
-- :*.h :^arch/*/include/uapi/asm/*.h :^include/uapi/ :^tools |
while read file
do
sed -i -e 's/(\(GPL-[^[:space:]]*\) WITH Linux-syscall-note)/\1/g' \
-e 's/ WITH Linux-syscall-note//g' $file
done
I did not commit drivers/staging/android/uapi/ion.h . This header is
not currently exported, but somebody may plan to move it to include/uapi/
when the time comes. I am not sure. Anyway, it will be better to check
the license inconsistency in drivers/staging/android/uapi/.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes gcc '-Wunused-but-set-variable' warning:
samples/vfio-mdev/mbochs.c: In function mbochs_ioctl:
samples/vfio-mdev/mbochs.c:1188:21: warning: variable mdev_state set but not used [-Wunused-but-set-variable]
It's not used any more since commit 104c7405a6 ("vfio:
add edid support to mbochs sample driver")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Make some structs and functions static to fix build warning, parts of
warning shown below,
samples/vfio-mdev/mtty.c:730:5: warning: symbol 'mtty_create' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:780:5: warning: symbol 'mtty_remove' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:802:5: warning: symbol 'mtty_reset' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:818:9: warning: symbol 'mtty_read' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:877:9: warning: symbol 'mtty_write' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:1070:5: warning: symbol 'mtty_get_region_info' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:1119:5: warning: symbol 'mtty_get_irq_info' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:1143:5: warning: symbol 'mtty_get_device_info' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:1275:5: warning: symbol 'mtty_open' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:1281:6: warning: symbol 'mtty_close' was not declared. Should it be static?
samples/vfio-mdev/mtty.c:1305:30: warning: symbol 'mtty_dev_groups' was not declared. Should it be static?
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Kirti Wankhede <kwankhede@nvidia.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[aw: wrap long lines]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Actually, total amount of available minor number
for a single major is MINORMARK + 1. So expand
minor range when registering chrdev region.
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Actually, total amount of available minor number
for a single major is MINORMARK + 1. So expand
minor range when registering chrdev region.
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Actually, total amount of available minor number
for a single major is MINORMARK + 1. So expand
minor range when registering chrdev region.
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There are new types and helpers that are supposed to be used in new code.
As a preparation to get rid of legacy types and API functions do
the conversion here.
Cc: Kirti Wankhede <kwankhede@nvidia.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Clang warns:
samples/vfio-mdev/mtty.c:592:39: warning: implicit conversion from 'int'
to 'char' changes value from 162 to -94 [-Wconstant-conversion]
*buf = UART_MSR_DSR | UART_MSR_DDSR | UART_MSR_DCD;
~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~
1 warning generated.
Turns out that all uses of buf in this function ultimately end up stored
or cast to an unsigned type. Just use u8, which has the same number of
bits but can store this larger number so Clang no longer warns.
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
mdev_access() calls mbochs_get_page() with mdev_state->ops_lock held,
while mbochs_get_page() locks the mutex by itself.
It leads to unavoidable deadlock.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There is no default implementation for dma_buf_ops->unmap.
So add a function unmapping the page, otherwise we'll leak them.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Atomic mapping interface for dmabufs will be removed.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Display device, demo-ing the vfio dmabuf display interface
(VFIO_GFX_PLANE_TYPE_DMABUF). Compatible enough to qemu stdvga
that bochs-drm.ko can be used as guest driver.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
When FIFO mode is enabled, the receive data available interrupt
(UART_IIR_RDI in code) should be triggered when the number of data
in FIFO is equal or larger than interrupt trigger level.
This patch changes the trigger level check to ensure multiple bytes
received from upper layer can trigger RDI interrupt correctly.
Cc: Joey Zheng <yu.zheng@hxt-semitech.com>
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Reviewed by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Make this const as it is only passed to a const argument of the function
mdev_register_device. Make it static as it is not referenced in any
other file.
Structure found using Coccinelle and changes done by hand.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We set info.count to 1 in mtty_get_irq_info() so static checkers
complain that, "Why do we have impossible conditions?" The answer is
that it seems to be left over dead code that can be safely removed.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is a sample driver for documentation so the impact is probably
pretty low. But we should check that bar_index is valid so we
don't write beyond the end of the mdev_state->region_info[] array.
Fixes: 9d1a546c53 ("docs: Sample driver to demonstrate how to use Mediated device framework.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The copy_to_user() function returns the number of bytes which it wasn't
able to copy but we want to return a negative error code.
Fixes: 9d1a546c53 ("docs: Sample driver to demonstrate how to use Mediated device framework.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is just sample code. We forget to set the error codes in a couple
places.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Abstract access to mdev_device so that we can define which interfaces
are public rather than relying on comments in the structure.
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Jike Song <jike.song@intel.com>
Reviewed by: Kirti Wankhede <kwankhede@nvidia.com>
Rather than hoping for good behavior by marking some elements
internal, enforce it by making the entire structure private and
creating an accessor function for the one useful external field.
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Jike Song <jike.song@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed by: Kirti Wankhede <kwankhede@nvidia.com>
Add an mdev_ prefix so we're not poluting the namespace so much.
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Jike Song <jike.song@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed by: Kirti Wankhede <kwankhede@nvidia.com>
This sample driver was originally under Documentation/ and was moved
to samples, but build support was never adjusted for the new location.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
The Sample driver creates mdev device that simulates serial port over PCI
card.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Marek Szyprowski
Huacai Chen
Jann Horn
Jani Nikula
Daniel Vetter
Parav Pandit
Masahiro Yamada
YueHaibing
Kefeng Wang
Thomas Gleixner
Chengguang Xu
Andy Shevchenko
Nathan Chancellor
Gerd Hoffmann
Alexey Khoroshilov
Souptick Joarder
Shunyong Yang
Bhumika Goyal
Dan Carpenter
Alex Williamson
Kirti Wankhede