Re: kern/45718 (processes sometimes get stuck and spin in vm_map)

[Taylor R Campbell <campbell+netbsd%mumble.net@localhost>]

The following reply was made to PR kern/45718; it has been noted by GNATS.

From: Taylor R Campbell <campbell+netbsd%mumble.net@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost,
        gnats-admin%netbsd.org@localhost, rmind%NetBSD.org@localhost
Subject: Re: kern/45718 (processes sometimes get stuck and spin in vm_map)
Date: Sat, 14 Apr 2012 16:57:01 +0000

 I caught some processes wedged in vm_map, although they don't seem to
 be spinning -- just wedged.  ps(1) reports these processes as zombies;
 top(1) does not report their taking any CPU time.  One is a subprocess
 of newsyslog; the other is a subprocess of git-pull.
 
 crash> t/a ca73daa0
 trace: pid 25970 lid 1 at 0xdc10781c
 sleepq_block(64,0,c0c5fd9d,c0ce63d0,0,0,0,c08e40d3,0,0) at sleepq_block+0xda
 cv_timedwait(c0d291d0,c0d291cc,64,dc1078e8,c0d28fe0,ffffffff,ffffffff,0,801=
 727,c66ef880) at cv_timedwait+0x126
 uvm_map_prepare(c0d291c0,c0000000,40000,c0d28fe0,ffffffff,ffffffff,0,801727=
 ,dc107928,dc107b54) at uvm_map_prepare+0x167
 uvm_map(c0d291c0,dc1079b0,40000,c0d28fe0,ffffffff,ffffffff,0,801727,800002,=
 0) at uvm_map+0x78
 uvm_km_alloc(c0d291c0,40000,0,800002,c0d15ea0,1,dc107a4c,c07e117a,c0d15ea0,=
 1) at uvm_km_alloc+0xe6
 exec_pool_alloc(c0d15ea0,1,dc107a0c,c09548fd,0,0,0,0,0,0) at exec_pool_allo=
 c+0x2b
 pool_grow(c0d15f14,1,c385ac12,0,0,c054,ca5ff000,c385ac09,9,c0d15f18) at poo=
 l_grow+0x2a
 pool_get(c0d15ea0,1,ce4e4a80,c098bb91,0,c31eec40,dc107adc,c056764b,c3137d00=
 ,c3137bc0) at pool_get+0x79
 execve_loadvm(8063f44,c055c480,dc107b3c,c3137d00,ca73daa0,0,8063f1c,c3ec440=
 0,c4519400,c380e000) at execve_loadvm+0x1da
 execve1(ca73daa0,8063f1c,8063f3c,8063f44,c055c480,6300,dc107d1c,0,c06ba833,=
 cd722744) at execve1+0x32
 sys_execve(ca73daa0,dc107cf4,dc107d1c,c08096f0,0,cdb17e3c,c0c8b800,dc107d30=
 ,c06babb9,cd722730) at sys_execve+0x30
 syscall(dc107d48,b3,ab,bfbf001f,806001f,8063f1c,8063f3c,bfbfec48,8063f1c,7d=
 7b7cff) at syscall+0x95
 
 crash> t/a ccc79540
 trace: pid 21497 lid 1 at 0xdc32581c
 sleepq_block(64,0,c0c5fd9d,c0ce63d0,0,0,0,c08e40d3,0,0) at sleepq_block+0xda
 cv_timedwait(c0d291d0,c0d291cc,64,dc3258e8,c0d28fe0,ffffffff,ffffffff,0,801=
 727,c66ef880) at cv_timedwait+0x126
 uvm_map_prepare(c0d291c0,c0000000,40000,c0d28fe0,ffffffff,ffffffff,0,801727=
 ,dc325928,dc325b54) at uvm_map_prepare+0x167
 uvm_map(c0d291c0,dc3259b0,40000,c0d28fe0,ffffffff,ffffffff,0,801727,800002,=
 0) at uvm_map+0x78
 uvm_km_alloc(c0d291c0,40000,0,800002,c0d15ea0,1,dc325a4c,c07e117a,c0d15ea0,=
 1) at uvm_km_alloc+0xe6
 exec_pool_alloc(c0d15ea0,1,dc325a0c,c09548fd,0,0,0,0,0,0) at exec_pool_allo=
 c+0x2b
 pool_grow(c0d15f14,1,c387f80b,0,0,c054,cd15fa80,c387f809,2,c0d15f18) at poo=
 l_grow+0x2a
 pool_get(c0d15ea0,1,c88faae0,c057c7e1,cda0986c,10,0,c3889700,ccc79540,0) at=
  pool_get+0x79
 execve_loadvm(bb92d404,c055c480,dc325b3c,c38b3e80,c30822f0,0,bb92d48c,c3ec5=
 c00,c3ec4800,ca9b9800) at execve_loadvm+0x1da
 execve1(ccc79540,bb92d48c,8063f9c,bb92d404,c055c480,106,dc325d3c,c0840430,0=
 ,0) at execve1+0x32
 sys_execve(ccc79540,dc325cf4,dc325d1c,c08096f0,0,cd722a78,c3663000,cda09868=
 ,0,bbb81010) at sys_execve+0x30
 syscall(dc325d48,bb9200b3,ab,bfbf001f,bbbb001f,bb92d48c,8063f9c,bfbfe1f8,bb=
 92d48c,bb92d49c) at syscall+0x95