Helge Deller d19f5e41b3 parisc: Clean up fixup routines for get_user()/put_user() ... Al Viro noticed that userspace accesses via get_user()/put_user() can be simplified a lot with regard to usage of the exception handling. This patch implements a fixup routine for get_user() and put_user() in such that the exception handler will automatically load -EFAULT into the register %r8 (the error value) in case on a fault on userspace. Additionally the fixup routine will zero the target register on fault in case of a get_user() call. The target register is extracted out of the faulting assembly instruction. This patch brings a few benefits over the old implementation: 1. Exception handling gets much cleaner, easier and smaller in size. 2. Helper functions like fixup_get_user_skip_1 (all of fixup.S) can be dropped. 3. No need to hardcode %r9 as target register for get_user() any longer. This helps the compiler register allocator and thus creates less assembler statements. 4. No dependency on the exception_data contents any longer. 5. Nested faults will be handled cleanly. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Cc: <stable@vger.kernel.org> # v4.9+ Signed-off-by: Helge Deller <deller@gmx.de>		2017-03-29 21:50:36 +02:00
..
fault.c	parisc: Clean up fixup routines for get_user()/put_user()	2017-03-29 21:50:36 +02:00
hugetlbpage.c	sched/headers: Prepare for new header dependencies before moving more code to <linux/sched/mm.h>	2017-03-02 08:42:30 +01:00
init.c	arch, mm: remove arch specific show_mem	2017-02-22 16:41:30 -08:00
ioremap.c
Makefile	parisc: Add Huge Page and HUGETLBFS support	2015-11-22 12:23:10 +01:00