On 3 May 2012 15:46, Sage Weil <sage@xxxxxxxxxxxx> wrote: > On Thu, 3 May 2012, Minchan Kim wrote: >> On 05/03/2012 04:46 AM, Andrew Morton wrote: >> > Well. What are we actually doing here? Causing the kernel to spew a >> > warning due to known-buggy callsites, so that users will report the >> > warnings, eventually goading maintainers into fixing their stuff. >> > >> > This isn't very efficient :( >> >> >> Yes. I hope maintainers fix it before merging this. >> >> > >> > It would be better to fix that stuff first, then add the warning to >> > prevent reoccurrences. Yes, maintainers are very naughty and probably >> > do need cattle prods^W^W warnings to motivate them to fix stuff, but we >> > should first make an effort to get these things fixed without >> > irritating and alarming our users. >> > >> > Where are these offending callsites? > > Okay, maybe this is a stupid question, but: if an fs can't call vmalloc > with GFP_NOFS without risking deadlock, calling with GFP_KERNEL instead > doesn't fix anything (besides being more honest). This really means that > vmalloc is effectively off-limits for file systems in any > writeback-related path, right? Anywhere it cannot reenter the filesystem, yes. GFP_NOFS is effectively GFP_KERNEL when calling vmalloc. Note that in writeback paths, a "good citizen" filesystem should not require any allocations, or at least it should be able to tolerate allocation failures. So fixing that would be a good idea anyway. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href