linux-kernel - 2.6.28.4 regression: mmap fails if mlockall used

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Message-ID: <20090208105222.hj7zhcyxyqfjeobt@m.safari.iki.fi>
Date:	Sun, 8 Feb 2009 12:52:22 +0200
From:	Sami Farin <safari-kernel@...ari.iki.fi>
To:	Linux kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: 2.6.28.4 regression: mmap fails if mlockall used

2.6.28.2 + gcc-4.3.2-7 works.
2.6.28.4 + gcc-4.4.0-0.16 does not work.
I run x86_64 SMP kernel.

# strace ./a.out ntp
12:10:14.780726 mmap(NULL, 2147624, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = -1 EFAULT (Bad address) <0.000038>
12:10:14.780809 close(3)                = 0 <0.000012>
12:10:14.780856 munmap(0x7f3476e0d000, 421232) = 0 <0.000145>
12:10:14.781054 write(2, "./a.out: getpwnam failed: Success\n"..., 34./a.out: getpwnam failed: Success
) = 34 <0.000015>

I can do malloc(3000000), then mmap call is
12:50:20.694207 mmap(NULL, 3002368, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f8a8d16b000 <0.003078>

-- 
"When playing Russian roulette, the fact that the first shot
 got off safely is little comfort for the next." - Richard Feynman


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