From: Andreas Schwab <schwab@suse.de>
To: qemu-devel@nongnu.org
Subject: qemu-x86_64 runs out of memory
Date: Tue, 13 Sep 2022 11:35:20 +0200 [thread overview]
Message-ID: <mvmczbzty5j.fsf@suse.de> (raw)
$ cat mmap.c
#include <stdio.h>
#include <sys/mman.h>
int
main (void)
{
void *A;
size_t L = 0, U, Max = 0;
for (U = 1; ; U *= 2)
{
A = mmap (0, U, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
if (A == (void *) -1)
break;
else
munmap (A, U);
}
while (L + 1 < U)
{
size_t M = L + (U - L) / 2;
A = mmap (0, M, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
if (A == (void *) -1)
U = M;
else
{
Max = M;
munmap(A, M);
L = M;
}
}
printf ("%zx\n", Max);
}
$ cc -O2 -g -Wall -std=gnu11 -g mmap.c -o mmap
$ ./mmap
7f672e5ff000
$ qemu-x86_64 ./mmap
Killed
--
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."
next reply other threads:[~2022-09-13 9:39 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-13 9:35 Andreas Schwab [this message]
2022-09-13 10:53 ` qemu-x86_64 runs out of memory Richard Henderson
2022-09-26 11:39 ` Li Zhang
2022-09-13 14:33 ` Alex Bennée
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