Re: [PATCH] Avoid overflows in kernel/time.c

From: H. Peter Anvin
Date: Mon Dec 10 2007 - 13:59:35 EST


Andrew Morton wrote:

My ia64 allmodconfig build has taken

akpm 15700 89.6 0.0 8256 700 pts/4 RN+ 03:09 10:41 bc -q kernel/timeconst.bc

11 minutes so far. fc6/x86_64.


I just tried this on my system, using your cross-compiler chain. I got a different error:

/opt/crosstool/gcc-3.4.5-glibc-2.3.6/ia64-unknown-linux-gnu/lib/gcc/ia64-unknown-linux-gnu/3.4.5/../../../../ia64-unknown-linux-gnu/bin/ld: section .data.patch [a000000000000500 -> a000000000000507] overlaps section .dynamic [a0000000000003c8 -> a000000000000507]
collect2: ld returned 1 exit status
make[2]: *** [arch/ia64/kernel/gate.so] Error 1

... but the timeconst stuff worked fine. I tried it both from the command line and using your xb script.

This is on a fc7/x86-64 box. I also ran through all the values from 48 to 1024 on both an fc5 and an fc7 box (no fc6 box readily available, although bc has been at 1.06 since 2000...)

In short, this is highly weird. Could you possibly do me a favour and just run, at the command line:

echo 250 | bc -q kernel/timeconst.bc

... and see if it reproduces the lockup (I'm assuming HZ == 250 in your config, since that's what I get when I do "make allmodconfig" on IA64.)

(No need to wait 11 minutes. It should run in a small fraction of a second.)

-hpa
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/