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Helge Deller 09b931fcb8 parisc: Clean up fixup routines for get_user()/put_user() ... commit d19f5e41b3 upstream. 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> Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		History 2017-04-08 09:30:34 +02:00
..
fault.c	parisc: Clean up fixup routines for get_user()/put_user()	2017-04-08 09:30:34 +02:00
hugetlbpage.c	mm: cleanup *pte_alloc* interfaces	2016-03-17 15:09:34 -07:00
init.c	parisc: Zero-initialize newly alloced memblock	2016-10-11 20:52:12 +02:00
ioremap.c	parisc: fix wrong page aligned size calculation in ioremapping code	2010-08-12 08:43:29 -07:00
Makefile	parisc: Add Huge Page and HUGETLBFS support	2015-11-22 12:23:10 +01:00