From mboxrd@z Thu Jan  1 00:00:00 1970
From: ratheesh k <ratheesh.ksz@gmail.com>
Subject: real time interrupts
Date: Wed, 13 Oct 2010 13:40:35 +0530
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I  am using 2.6.18 kernel with rt-linux patch. In my userspace program
, I registered for signals  65,64,63,62 ( timer  ) . In my signal
handler , i have a call to localtime(). local_time() seems to be
invoking an io call.

program seems to be frozen , when all interrupts comes together. i
could see from the core ( grenerated forcifully using ABRT signal )
that all signal handler acquire some lock and suddently some other
inteerupt comes....this leads to deadlock


#15 <signal handler called>
#16 0x0070a886 in _IO_vfscanf_internal () from /lib/libc.so.6
#17 0x007170c1 in vsscanf () from /lib/libc.so.6
#18 0x00711dae in sscanf () from /lib/libc.so.6
#19 0x0073ff9f in __tzset_parse_tz () from /lib/libc.so.6
#20 0x00740f8f in __tzfile_compute () from /lib/libc.so.6
#21 0x00740845 in __tz_convert () from /lib/libc.so.6
#22 0x0073ecff in localtime () from /lib/libc.so.6

How to get away from this ?