Messages in this thread |  | | | Date | Fri, 4 Nov 2005 16:08:51 -0800 | | From | Andrew Morton <> | | Subject | Re: [PATCH resubmit] do_mount: reduce stack consumption |
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Adrian Bunk <bunk@stusta.de> wrote: > > On Fri, Nov 04, 2005 at 10:27:42PM +0100, Heiko Carstens wrote: > > > > See original stack back trace below and Andreas' patch and analysis > > > > here: > > > > http://www.ussg.iu.edu/hypermail/linux/kernel/0410.3/1844.html > > > > I probably should add that with "original" stack back trace a trace of > > a 2.6.10 kernel was meant, if that wasn't clear, but the DM code is > > still the same in 2.6.14. > > > > > > <4>Call Trace: > > ... > > > > <4> [<0000000010831380>] __map_bio+0x70/0x160 [dm_mod] > > > > <4> [<000000001083173e>] __split_bio+0x1e6/0x538 [dm_mod] > > > > <4> [<0000000010831ba8>] dm_request+0x118/0x25c [dm_mod] > > > > <4> [<0000000000241074>] generic_make_request+0xf0/0x21c > > > > <4> [<0000000010831380>] __map_bio+0x70/0x160 [dm_mod] > > > > <4> [<000000001083173e>] __split_bio+0x1e6/0x538 [dm_mod] > > > > <4> [<0000000010831ba8>] dm_request+0x118/0x25c [dm_mod] > > > > <4> [<0000000000241074>] generic_make_request+0xf0/0x21c > > > > <4> [<0000000010831380>] __map_bio+0x70/0x160 [dm_mod] > > > > <4> [<000000001083173e>] __split_bio+0x1e6/0x538 [dm_mod] > > > > <4> [<0000000010831ba8>] dm_request+0x118/0x25c [dm_mod] > > > > <4> [<0000000000241074>] generic_make_request+0xf0/0x21c > > ... > > > > This part of the call trace is actually good for >1500 bytes of stack > > usage and is what kills us and should be fixed. > > I'm surprised that there are no other bug reports regarding DM and > > stack overflow with 4k stacks. > >... > > There were some reports of dm+xfs overflows with 4k stacks on i386. > > The xfs side was sorted out, but I son't know the state of the dm part. >
The state is Very Bad, IMO. At the very least, DM should struggle to the utmost to reduce the stack utilisation around that recursion point. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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