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

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

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,0,801727,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_alloc+0x2b
pool_grow(c0d15f14,1,c385ac12,0,0,c054,ca5ff000,c385ac09,9,c0d15f18) at 
pool_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,c3ec4400,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,7d7b7cff)
 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,0,801727,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_alloc+0x2b
pool_grow(c0d15f14,1,c387f80b,0,0,c054,cd15fa80,c387f809,2,c0d15f18) at 
pool_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,c3ec5c00,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,bb92d48c,bb92d49c)
 at syscall+0x95