mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-01-16 01:39:45 -05:00
59e8a1ce8f
In subsequent patches we want to explciitly annotate uaccess fixups in
assembly files.
We have existing helpers for this for inline assembly, but due to
differing stringification requirements it's not possible to have a
single definition that we can use for both inline asm and plain asm
files. So as with other cases (e.g. gpr-regnum.h), we must prove
separate helprs for plain asm and inline asm.
So that we can do so, this patch adds helpers to define
EX_TYPE_UACCESS_ERR_ZERO fixups in plain assembly. These correspond 1-1
with the inline assembly versions except for the absence of
stringification. No plain assmebly heleprs are added for
EX_TYPE_LOAD_UNALIGNED_ZEROPAD fixups as these only exist for a single C
function.
For copy_{to,from}_user() we'll need fixups with regs and err, so I've
added _ASM_EXTABLE_UACCESS(insn, fixup), where both the error and zero
registers are WZR.
For clarity, the existing `_asm_extable` assemgbly maco is now defined
in terms of the _ASM_EXTABLE() CPP macro, making the CPP macros
canonical in all cases.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
Link: https://lore.kernel.org/r/20220621072638.1273594-4-tongtiangen@huawei.com
Signed-off-by: Will Deacon <will@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.