Revision 10f1d5d111e8aed46a0f1179faf9a3cf422f689e authored by Joe Thornber on 27 June 2014, 19:29:04 UTC, committed by Mike Snitzer on 10 July 2014, 20:44:14 UTC
There's a race condition between the atomic_dec_and_test(&io->count) in dec_count() and the waking of the sync_io() thread. If the thread is spuriously woken immediately after the decrement it may exit, making the on stack io struct invalid, yet the dec_count could still be using it. Fix this race by using a completion in sync_io() and dec_count(). Reported-by: Minfei Huang <huangminfei@ucloud.cn> Signed-off-by: Joe Thornber <thornber@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org
1 parent bf14299
mksysmap
#!/bin/sh -x
# Based on the vmlinux file create the System.map file
# System.map is used by module-init tools and some debugging
# tools to retrieve the actual addresses of symbols in the kernel.
#
# Usage
# mksysmap vmlinux System.map
#####
# Generate System.map (actual filename passed as second argument)
# $NM produces the following output:
# f0081e80 T alloc_vfsmnt
# The second row specify the type of the symbol:
# A = Absolute
# B = Uninitialised data (.bss)
# C = Common symbol
# D = Initialised data
# G = Initialised data for small objects
# I = Indirect reference to another symbol
# N = Debugging symbol
# R = Read only
# S = Uninitialised data for small objects
# T = Text code symbol
# U = Undefined symbol
# V = Weak symbol
# W = Weak symbol
# Corresponding small letters are local symbols
# For System.map filter away:
# a - local absolute symbols
# U - undefined global symbols
# N - debugging symbols
# w - local weak symbols
# readprofile starts reading symbols when _stext is found, and
# continue until it finds a symbol which is not either of 'T', 't',
# 'W' or 'w'. __crc_ are 'A' and placed in the middle
# so we just ignore them to let readprofile continue to work.
# (At least sparc64 has __crc_ in the middle).
$NM -n $1 | grep -v '\( [aNUw] \)\|\(__crc_\)\|\( \$[adt]\)' > $2
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