RE: Panics instead of Hard Locks

2002-11-11 Thread John Baldwin 

On 09-Nov-2002 Joel M. Baldwin wrote:
 
 Since going from a SMP to nonSMP kernel the Hard Locks don't
 seem to be happening.  However I'm getting panics.
 
 I've gotten 4 'sleeping thread owns a mutex' panics and one each
 of 'Assertion i != 0 failed at ../../../kern/subr_witness.c:669'
 and 'Duplicate free of item 0xc3895cc0 from zone 0xc0ea63c0(VMSPACE)'
 
 More info follows.  I finally got a debugger kernel built so I'll
 have even more info after the next panic.  Let me know what I can
 do to help.
 
 --
 
 
 panic: Assertion i != 0 failed at ../../../kern/subr_witness.c:669
 Debugger(panic)
 Stopped at  Debugger+0x54:  xchgl   %ebx,in_Debugger.0
 db bt
 No such command
 db x
 Debugger+0x54:  29401d87
 db t
 Debugger(c038693f,c03f6020,c0389a7b,cd2e2b00,1) at Debugger+0x54
 panic(c0389a7b,c0389cee,c038993f,29d,cd2e2b64) at panic+0xab
 witness_lock(c03c29a0,8,c0386f4e,134,c0385a95) at witness_lock+0x513
 _mtx_lock_flags(c03c29a0,0,c0386f4e,134,cd2e2b90) at 
 _mtx_lock_flags+0xb1
 msleep(c265d504,c03f4974,44,c039acd9,0) at msleep+0x644
 acquire(c265d504,100,600,e3,5) at acquire+0xa7
 lockmgr(c265d504,2,0,c0eadea0,cd2e2c2c) at lockmgr+0x378
 _vm_map_lock_read(c265d4c8,c039ad3c,153,c0385a95,c265c700) at 
 _vm_map_lock_read+0x5b
 vmspace_swap_count(c265d4c8,0,c039c4d2,493,0) at vmspace_swap_count+0x29
 vm_pageout_scan(0,0,44,c039c590,1f4) at vm_pageout_scan+0xa48
 vm_pageout(0,cd2e2d48,c0384133,354,0) at vm_pageout+0x262
 fork_exit(c03163b0,0,cd2e2d48) at fork_exit+0xa5
 fork_trampoline() at fork_trampoline+0x1a
 --- trap 0x1, eip = 0, esp = 0xcd2e2d7c, ebp = 0 ---

*sigh*,  This is a bogus assertion and my fault.  I'll fix it.  Thanks!

-- 

John Baldwin [EMAIL PROTECTED]http://www.FreeBSD.org/~jhb/
Power Users Use the Power to Serve!  -  http://www.FreeBSD.org/

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Re: Panics instead of Hard Locks

2002-11-10 Thread Tor . Egge 
 
 Since going from a SMP to nonSMP kernel the Hard Locks don't
 seem to be happening.  However I'm getting panics.
 
 I've gotten 4 'sleeping thread owns a mutex' panics and one each
 of 'Assertion i != 0 failed at ../../../kern/subr_witness.c:669'
 and 'Duplicate free of item 0xc3895cc0 from zone 0xc0ea63c0(VMSPACE)'

The 'Duplicate free' can be caused by a race between swapout_procs()
and kern_exit()+wait1().

The enclosed patch might help.

Disabling swapping (sysctl vm.swap_enabled=0) can also help.

- Tor Egge

Index: sys/kern/kern_exit.c
===
RCS file: /home/ncvs/src/sys/kern/kern_exit.c,v
retrieving revision 1.184
diff -u -r1.184 kern_exit.c
--- sys/kern/kern_exit.c15 Oct 2002 00:14:32 -  1.184
+++ sys/kern/kern_exit.c10 Nov 2002 17:58:39 -
 -285,7 +285,7 
 * Can't free the entire vmspace as the kernel stack
 * may be mapped within that space also.
 */
-   if (--vm-vm_refcnt == 0) {
+   if (vm-vm_refcnt == 1) {
if (vm-vm_shm)
shmexit(p);
pmap_remove_pages(vmspace_pmap(vm), vm_map_min(vm-vm_map),
Index: sys/vm/vm_map.c
===
RCS file: /home/ncvs/src/sys/vm/vm_map.c,v
retrieving revision 1.271
diff -u -r1.271 vm_map.c
--- sys/vm/vm_map.c 9 Nov 2002 21:26:49 -   1.271
+++ sys/vm/vm_map.c 10 Nov 2002 17:59:40 -
 -314,11 +317,9 
struct vmspace *vm;
 
GIANT_REQUIRED;
-   if (p == p-p_vmspace-vm_freer) {
-   vm = p-p_vmspace;
-   p-p_vmspace = NULL;
-   vmspace_dofree(vm);
-   }
+   vm = p-p_vmspace;
+   p-p_vmspace = NULL;
+   vmspace_free(vm);
 }
 
 /*

Re: Panics instead of Hard Locks

2002-11-10 Thread Joel M. Baldwin 

If there's a race why hasn't it been fixed in the main tree?

A swap issue makes sense.  If I've been down long enough I get
swamped with email when I come back up.  A bug in the latest
procmail yields 130M processes that fill up swap and make
the system be swap bound.  The solution is the following
patch to procmail.

http://www.rosat.mpe-garching.mpg.de/mailing-lists/procmail/2002-04/ms
g00248.html

--On Sunday, November 10, 2002 7:03 PM + 
[EMAIL PROTECTED] wrote:


Since going from a SMP to nonSMP kernel the Hard Locks don't
seem to be happening.  However I'm getting panics.

I've gotten 4 'sleeping thread owns a mutex' panics and one each
of 'Assertion i != 0 failed at ../../../kern/subr_witness.c:669'
and 'Duplicate free of item 0xc3895cc0 from zone 0xc0ea63c0(VMSPACE)'


The 'Duplicate free' can be caused by a race between swapout_procs()
and kern_exit()+wait1().

The enclosed patch might help.

Disabling swapping (sysctl vm.swap_enabled=0) can also help.

- Tor Egge





To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message

Panics instead of Hard Locks

2002-11-09 Thread Joel M. Baldwin 

Since going from a SMP to nonSMP kernel the Hard Locks don't
seem to be happening.  However I'm getting panics.

I've gotten 4 'sleeping thread owns a mutex' panics and one each
of 'Assertion i != 0 failed at ../../../kern/subr_witness.c:669'
and 'Duplicate free of item 0xc3895cc0 from zone 0xc0ea63c0(VMSPACE)'

More info follows.  I finally got a debugger kernel built so I'll
have even more info after the next panic.  Let me know what I can
do to help.

--


panic: Assertion i != 0 failed at ../../../kern/subr_witness.c:669
Debugger(panic)
Stopped at  Debugger+0x54:  xchgl   %ebx,in_Debugger.0
db bt
No such command
db x
Debugger+0x54:  29401d87
db t
Debugger(c038693f,c03f6020,c0389a7b,cd2e2b00,1) at Debugger+0x54
panic(c0389a7b,c0389cee,c038993f,29d,cd2e2b64) at panic+0xab
witness_lock(c03c29a0,8,c0386f4e,134,c0385a95) at witness_lock+0x513
_mtx_lock_flags(c03c29a0,0,c0386f4e,134,cd2e2b90) at 
_mtx_lock_flags+0xb1
msleep(c265d504,c03f4974,44,c039acd9,0) at msleep+0x644
acquire(c265d504,100,600,e3,5) at acquire+0xa7
lockmgr(c265d504,2,0,c0eadea0,cd2e2c2c) at lockmgr+0x378
_vm_map_lock_read(c265d4c8,c039ad3c,153,c0385a95,c265c700) at 
_vm_map_lock_read+0x5b
vmspace_swap_count(c265d4c8,0,c039c4d2,493,0) at vmspace_swap_count+0x29
vm_pageout_scan(0,0,44,c039c590,1f4) at vm_pageout_scan+0xa48
vm_pageout(0,cd2e2d48,c0384133,354,0) at vm_pageout+0x262
fork_exit(c03163b0,0,cd2e2d48) at fork_exit+0xa5
fork_trampoline() at fork_trampoline+0x1a
--- trap 0x1, eip = 0, esp = 0xcd2e2d7c, ebp = 0 ---



panic: Duplicate free of item 0xc3895cc0 from zone 0xc0ea63c0(VMSPACE)

Debugger(panic)
Stopped at  Debugger+0x54:  xchgl   %ebx,in_Debugger.0
db t
Debugger(c038693f,c03f6020,c039cbea,cdccac4c,1) at Debugger+0x54
panic(c039cbea,c3895cc0,c0ea63c0,c039ad51,693) at panic+0xab
uma_dbg_free(c0ea63c0,0,c3895cc0,693,0) at uma_dbg_free+0x122
uma_zfree_arg(c0ea63c0,c3895cc0,0,12d,c2f75e00) at uma_zfree_arg+0xfa
vmspace_free(c3895cc0,c039a9c3,31d,31c,186a0) at vmspace_free+0xbe
swapout_procs(1,0,68,c039c590,0) at swapout_procs+0x387
vm_daemon(0,cdccad48,c0384133,354,0) at vm_daemon+0x6e
fork_exit(c03166b0,0,cdccad48) at fork_exit+0xa5
fork_trampoline() at fork_trampoline+0x1a
--- trap 0x1, eip = 0, esp = 0xcdccad7c, ebp = 0 ---

--


panic: sleeping thread owns a mutex
Debugger(panic)
Stopped at  Debugger+0x54:  xchgl   %ebx,in_Debugger.0
db t
Debugger(c038693f,c03f6020,c0385b1e,cd29ac14,1) at Debugger+0x54
panic(c0385b1e,1,c0385a95,6b,0) at panic+0xab
propagate_priority(c0eaca90,2,c0385a95,23b,c0eaca90) at 
propagate_priority+0x13c
_mtx_lock_sleep(c2c090b0,0,c0392b8d,182,c03f90f8) at 
_mtx_lock_sleep+0x219
_mtx_lock_flags(c2c090b0,0,c0392b8d,182,c038760b) at 
_mtx_lock_flags+0x97
syncache_timer(0,0,c038760b,bf,2edb5a) at syncache_timer+0xaf
softclock(0,0,c03843cc,230,c0eaba80) at softclock+0x19c
ithread_loop(c0e9fa00,cd29ad48,c0384133,354,0) at ithread_loop+0x182
fork_exit(c01fb6b0,c0e9fa00,cd29ad48) at fork_exit+0xa5
fork_trampoline() at fork_trampoline+0x1a
--- trap 0x1, eip = 0, esp = 0xcd29ad7c, ebp = 0 ---

-

panic: sleeping thread owns a mutex
Debugger(panic)
Stopped at  Debugger+0x54:  xchgl   %ebx,in_Debugger.0
db t
Debugger(c038693f,c03f6020,c0385b1e,cd29ac14,1) at Debugger+0x54
panic(c0385b1e,1,c0385a95,6b,0) at panic+0xab
propagate_priority(c0eaca90,2,c0385a95,23b,c0eaca90) at 
propagate_priority+0x13c
_mtx_lock_sleep(c2da9c7c,0,c0392b8d,182,c03f90f8) at 
_mtx_lock_sleep+0x219
_mtx_lock_flags(c2da9c7c,0,c0392b8d,182,c038760b) at 
_mtx_lock_flags+0x97
syncache_timer(0,0,c038760b,bf,20be24) at syncache_timer+0xaf
softclock(0,0,c03843cc,230,c0eaba80) at softclock+0x19c
ithread_loop(c0e9fa00,cd29ad48,c0384133,354,0) at ithread_loop+0x182
fork_exit(c01fb6b0,c0e9fa00,cd29ad48) at fork_exit+0xa5
fork_trampoline() at fork_trampoline+0x1a
--- trap 0x1, eip = 0, esp = 0xcd29ad7c, ebp = 0 ---

-

anic: sleeping thread owns a mutex
Debugger(panic)
Stopped at  Debugger+0x54:  xchgl   %ebx,in_Debugger.0
db t
Debugger(c038693f,c03f6020,c0385b1e,cd29ac14,1) at Debugger+0x54
panic(c0385b1e,1,c0385a95,6b,0) at panic+0xab
propagate_priority(c0eaca90,2,c0385a95,23b,c0eaca90) at 
propagate_priority+0x13c
_mtx_lock_sleep(c2f630b0,0,c0392b8d,182,c03f90f8) at 
_mtx_lock_sleep+0x219
_mtx_lock_flags(c2f630b0,0,c0392b8d,182,c038760b) at 
_mtx_lock_flags+0x97
syncache_timer(2,0,c038760b,bf,124b9a) at syncache_timer+0xaf
softclock(0,0,c03843cc,230,c0eaba80) at softclock+0x19c
ithread_loop(c0e9fa00,cd29ad48,c0384133,354,0) at ithread_loop+0x182
fork_exit(c01fb6b0,c0e9fa00,cd29ad48) at fork_exit+0xa5
fork_trampoline() at fork_trampoline+0x1a
--- trap 0x1, eip = 0, esp = 0xcd29ad7c, ebp = 0 ---