Re: CVS commit: src/sys/netinet

[Tom Ivar Helbekkmo <tih%hamartun.priv.no@localhost>]

Ryota Ozaki <ozaki-r%NetBSD.org@localhost> writes:

> I think the below patch fixes the above issue, but probably
> there is a better solution.

Looks like didn't -- it just changed it a little bit.  Just like the
last time, the hang happened while reading email over IMAP, which
exercises disk and network at the same time, while the machine was busy
doing a parallellized system build in the background.  This time,
though, I got a core dump.  Here's the hang (the active process on this
CPU is the IMAP server):

__cpu_simple_lock_try() at __cpu_simple_lock_try+0x9
pool_grow() at pool_grow+0x55d
pool_catchup() at pool_catchup+0x32
pool_get() at pool_get+0x492
pool_cache_get_slow() at pool_cache_get_slow+0x1b4
pool_cache_get_paddr() at pool_cache_get_paddr+0x275
m_get() at m_get+0x2a
m_gethdr() at m_gethdr+0x9
wm_add_rxbuf() at wm_add_rxbuf+0x3a
wm_rxeof() at wm_rxeof+0x146
wm_intr_legacy() at wm_intr_legacy+0xa1
intr_biglock_wrapper() at intr_biglock_wrapper+0x1d
Xintr_ioapic_level2() at Xintr_ioapic_level2+0xf7
--- interrupt ---
Xspllower() at Xspllower+0xe
uvm_km_kmem_alloc() at uvm_km_kmem_alloc+0x139
pool_page_alloc() at pool_page_alloc+0x2c
pool_grow() at pool_grow+0x24f
pool_catchup() at pool_catchup+0x32
pool_get() at pool_get+0x492
pool_cache_get_slow() at pool_cache_get_slow+0x1b4
pool_cache_get_paddr() at pool_cache_get_paddr+0x275
m_get() at m_get+0x2a
m_gethdr() at m_gethdr+0x9
sosend() at sosend+0x35a
soo_write() at soo_write+0x2c
dofilewrite() at dofilewrite+0x97
sys_write() at sys_write+0x5f
syscall() at syscall+0x1d8
--- syscall (number 4) ---

The only other CPU that looks interesting has this (copied from a
photograph of the console, as crash(8) doesn't know about CPUs):

_kernel_lock()
ip_slowtimo()
pfslowtimo()
callout_softclock()
softint_dispatch()

The two remaining ones are in x86_pause(), waiting for I/O.

-tih
-- 
Most people who graduate with CS degrees don't understand the significance
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