malloc fallout and linprocfs

[Steve Kargl]

On Tue, Jan 17, 2006 at 12:50:06PM -0800, Jason Evans wrote:
> On Jan 17, 2006, at 12:41 PM, Steve Kargl wrote:
> >If I fire up a linux version of OpenOffice on amd64, I see
> >several messages of the following form on the console.
> >
> >KDB: stack backtrace:
> >witness_warn() at witness_warn+0x262
> >uma_zalloc_arg() at uma_zalloc_arg+0x217
> >malloc() at malloc+0xa3
> >vn_fullpath() at vn_fullpath+0x56
> >linprocfs_doprocmaps() at linprocfs_doprocmaps+0x31e
> >pfs_read() at pfs_read+0x260
> >VOP_READ_APV() at VOP_READ_APV+0x74
> >vn_read() at vn_read+0x14f
> >dofileread() at dofileread+0x94
> >kern_readv() at kern_readv+0x60
> >read() at read+0x4a
> >ia32_syscall() at ia32_syscall+0x178
> >Xint0x80_syscall() at Xint0x80_syscall+0x5d
> >malloc(M_WAITOK) of "1024", forcing M_NOWAIT with the following non- 
> >sleepable locks held:
> >exclusive sleep mutex vm object (standard object) r = 0  
> >(0xffffff02b7846640) locked @ /usr/src/sys/compat/linprocfs/ 
> >linprocfs.c:874
> >
> >This is with
> >troutmask:kargl[202] ident /usr/src/lib/libc/stdlib/malloc.c
> >/usr/src/lib/libc/stdlib/malloc.c:
> >$FreeBSD: src/lib/libc/stdlib/malloc.c,v 1.92 2006/01/12 18:09:25  
> >jasone Exp $
> 
> I don't think that libc's malloc is a factor here; the stacktrace  
> above is all in the kernel, isn't it?
> 

You're probably right, but I wasn't sure whether "malloc at malloc+0xa3"
was the kernel malloc or your new allocator.  Either way, I need to 
update to 1.95.  I should also note that this is the first time I've
seen this trace, which could be a coincident with respect to your malloc.

-- 
Steve