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
checkversion.pl
#! /usr/bin/perl
#
# checkversion find uses of LINUX_VERSION_CODE or KERNEL_VERSION
# without including <linux/version.h>, or cases of
# including <linux/version.h> that don't need it.
# Copyright (C) 2003, Randy Dunlap <rdunlap@xenotime.net>
use strict;
$| = 1;
my $debugging;
foreach my $file (@ARGV) {
next if $file =~ "include/linux/version\.h";
# Open this file.
open( my $f, '<', $file )
or die "Can't open $file: $!\n";
# Initialize variables.
my ($fInComment, $fInString, $fUseVersion);
my $iLinuxVersion = 0;
while (<$f>) {
# Strip comments.
$fInComment && (s+^.*?\*/+ +o ? ($fInComment = 0) : next);
m+/\*+o && (s+/\*.*?\*/+ +go, (s+/\*.*$+ +o && ($fInComment = 1)));
# Pick up definitions.
if ( m/^\s*#/o ) {
$iLinuxVersion = $. if m/^\s*#\s*include\s*"linux\/version\.h"/o;
}
# Strip strings.
$fInString && (s+^.*?"+ +o ? ($fInString = 0) : next);
m+"+o && (s+".*?"+ +go, (s+".*$+ +o && ($fInString = 1)));
# Pick up definitions.
if ( m/^\s*#/o ) {
$iLinuxVersion = $. if m/^\s*#\s*include\s*<linux\/version\.h>/o;
}
# Look for uses: LINUX_VERSION_CODE, KERNEL_VERSION, UTS_RELEASE
if (($_ =~ /LINUX_VERSION_CODE/) || ($_ =~ /\WKERNEL_VERSION/)) {
$fUseVersion = 1;
last if $iLinuxVersion;
}
}
# Report used version IDs without include?
if ($fUseVersion && ! $iLinuxVersion) {
print "$file: $.: need linux/version.h\n";
}
# Report superfluous includes.
if ($iLinuxVersion && ! $fUseVersion) {
print "$file: $iLinuxVersion linux/version.h not needed.\n";
}
# debug: report OK results:
if ($debugging) {
if ($iLinuxVersion && $fUseVersion) {
print "$file: version use is OK ($iLinuxVersion)\n";
}
if (! $iLinuxVersion && ! $fUseVersion) {
print "$file: version use is OK (none)\n";
}
}
close($f);
}
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