Reference in a new issue

Blame

Copy permalink

Reference in a new issue

Copy permalink

David S. Miller 62268585e5 sparc64: Fix several bugs in memmove(). ... [ Upstream commit 2077cef4d5 ] Firstly, handle zero length calls properly. Believe it or not there are a few of these happening during early boot. Next, we can't just drop to a memcpy() call in the forward copy case where dst <= src. The reason is that the cache initializing stores used in the Niagara memcpy() implementations can end up clearing out cache lines before we've sourced their original contents completely. For example, considering NG4memcpy, the main unrolled loop begins like this: load src + 0x00 load src + 0x08 load src + 0x10 load src + 0x18 load src + 0x20 store dst + 0x00 Assume dst is 64 byte aligned and let's say that dst is src - 8 for this memcpy() call. That store at the end there is the one to the first line in the cache line, thus clearing the whole line, which thus clobbers "src + 0x28" before it even gets loaded. To avoid this, just fall through to a simple copy only mildly optimized for the case where src and dst are 8 byte aligned and the length is a multiple of 8 as well. We could get fancy and call GENmemcpy() but this is good enough for how this thing is actually used. Reported-by: David Ahern <david.ahern@oracle.com> Reported-by: Bob Picco <bpicco@meloft.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>		History 2015-03-24 08:22:10 -04:00
..
boot	sparc: Add "install" target	2014-08-04 20:45:59 -07:00
configs	sparc: Set CONFIG_NET=y in defconfigs	2014-09-24 13:38:30 -04:00
crypto	crypto: prefix module autoloading with "crypto-"	2015-01-29 17:40:46 -08:00
include	sparc: Add NOP dma_cache_sync() implementation.	2014-11-26 13:36:41 -08:00
kernel	sparc: Touch NMI watchdog when walking cpus and calling printk	2015-03-24 08:22:10 -04:00
lib	sparc64: Fix several bugs in memmove().	2015-03-24 08:22:10 -04:00
math-emu	arch/sparc/math-emu/math_32.c: drop stray break operator	2014-08-04 20:29:06 -07:00
mm	sparc32: destroy_context() and switch_mm() needs to disable interrupts.	2015-03-24 08:22:08 -04:00
net	sparc: bpf_jit: add support for BPF_LD(X) | BPF_LEN instructions	2014-09-26 16:52:09 -04:00
oprofile	sparc: using HZ needs an include of linux/param.h	2009-10-05 00:46:08 -07:00
power	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc	2014-10-11 20:36:34 -04:00
prom	sparc64: Fix register corruption in top-most kernel stack frame during boot.	2014-10-24 09:52:49 -07:00
Kbuild	sparc64: Add SHA1 driver making use of the 'sha1' instruction.	2012-08-20 15:08:49 -07:00
Kconfig	sparc64: sparse irq	2014-10-05 16:53:40 -07:00
Kconfig.debug	lib: consolidate DEBUG_STACK_USAGE option	2011-05-25 08:39:54 -07:00
Makefile	sparc: Add "install" target	2014-08-04 20:45:59 -07:00