mirror of
https://github.com/raspberrypi/linux.git
synced 2025-12-06 01:49:46 +00:00
11beda187b
Provide a __copy_from_user that uses memcpy. On BCM2708, use optimised memcpy/memmove/memcmp/memset implementations. arch/arm: Add mmiocpy/set aliases for memcpy/set See: https://github.com/raspberrypi/linux/issues/1082 copy_from_user: CPU_SW_DOMAIN_PAN compatibility The downstream copy_from_user acceleration must also play nice with CONFIG_CPU_SW_DOMAIN_PAN. See: https://github.com/raspberrypi/linux/issues/1381 Signed-off-by: Phil Elwell <phil@raspberrypi.org> Fix copy_from_user if BCM2835_FAST_MEMCPY=n The change which introduced CONFIG_BCM2835_FAST_MEMCPY unconditionally changed the behaviour of arm_copy_from_user. The page pinning code is not safe on ARMv7 if LPAE & high memory is enabled and causes crashes which look like PTE corruption. Make __copy_from_user_memcpy conditional on CONFIG_2835_FAST_MEMCPY=y which is really an ARMv6 / Pi1 optimization and not necessary on newer ARM processors. arm: fix mmap unlocks in uaccess_with_memcpy.c This is a regression that was added with the commit192a4e923eas of rpi-5.8.y, since that is when the move to the mmap locking API was introduced -d8ed45c5dcThe issue is that when the patch to improve performance for the __copy_to_user and __copy_from_user functions were added for the Raspberry Pi, some of the mmaps were incorrectly mapped to write instead of read. This would cause a verity of issues, and in my case, prevent the booting of a squashfs filesystem on rpi-5.8-y and above. An example of the panic you would see from this can be seen at https://pastebin.com/raw/jBz5xCzL Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Signed-off-by: Christopher Blake <chrisrblake93@gmail.com> arch/arm: Add __memset alias to memset_rpi.S memset_rpi.S is an optimised memset implementation, but doesn't define __memset (which was just added to memset.S). As a result, building for the BCM2835 platform causes a link failure. Add __memset as yet another alias to our common implementation. Signed-off-by: Phil Elwell <phil@raspberrypi.com> arm: Fix custom rpi __memset32 and __memset64 See: https://github.com/raspberrypi/linux/issues/4798 Signed-off-by: Phil Elwell <phil@raspberrypi.com> arm: Fix annoying .eh_frame section warnings Replace the cfi directives with the UNWIND equivalents. This prevents the .eh_frame section from being created, eliminating the warnings. Signed-off-by: Phil Elwell <phil@raspberrypi.com>
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.