Vincent Whitchurch 344eb5539a ARM: 8813/1: Make aligned 2-byte getuser()/putuser() atomic on ARMv6+ ... getuser() and putuser() (and there underscored variants) use two strb[t]/ldrb[t] instructions when they are asked to get/put 16-bits. This means that the read/write is not atomic even when performed to a 16-bit-aligned address. This leads to problems with vhost: vhost uses __getuser() to read the vring's 16-bit avail.index field, and if it happens to observe a partial update of the index, wrong descriptors will be used which will lead to a breakdown of the virtio communication. A similar problem exists for __putuser() which is used to write to the vring's used.index field. The reason these functions use strb[t]/ldrb[t] is because strht/ldrht instructions did not exist until ARMv6T2/ARMv7. So we should be easily able to fix this on ARMv7. Also, since all ARMv6 processors also don't actually use the unprivileged instructions anymore for uaccess (since CONFIG_CPU_USE_DOMAINS is not used) we can easily fix them too. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>		2018-11-12 10:52:04 +00:00
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ashldi3.S
ashrdi3.S
backtrace.S
bitops.h
bswapsdi2.S
call_with_stack.S
changebit.S
clear_user.S
clearbit.S
copy_from_user.S
copy_page.S
copy_template.S
copy_to_user.S
csumipv6.S
csumpartial.S
csumpartialcopy.S
csumpartialcopygeneric.S
csumpartialcopyuser.S
delay-loop.S
delay.c
div64.S
ecard.S
findbit.S
floppydma.S
getuser.S	ARM: 8813/1: Make aligned 2-byte getuser()/putuser() atomic on ARMv6+	2018-11-12 10:52:04 +00:00
io-acorn.S
io-readsb.S
io-readsl.S
io-readsw-armv3.S
io-readsw-armv4.S
io-writesb.S
io-writesl.S
io-writesw-armv3.S
io-writesw-armv4.S
lib1funcs.S
lshrdi3.S
Makefile
memchr.S
memcpy.S
memmove.S
memset.S
muldi3.S
putuser.S	ARM: 8813/1: Make aligned 2-byte getuser()/putuser() atomic on ARMv6+	2018-11-12 10:52:04 +00:00
setbit.S
strchr.S
strrchr.S
testchangebit.S
testclearbit.S
testsetbit.S
uaccess_with_memcpy.c
ucmpdi2.S
xor-neon.c