Date: Thu, 20 May 2010 21:07:58 +0000 (UTC) From: Nathan Whitehorn <nwhitehorn@FreeBSD.org> To: cvs-src-old@freebsd.org Subject: cvs commit: src/sys/powerpc/aim ofw_machdep.c Message-ID: <201005202108.o4KL8FOq098411@repoman.freebsd.org>
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nwhitehorn 2010-05-20 21:07:58 UTC
FreeBSD src repository
Modified files:
sys/powerpc/aim ofw_machdep.c
Log:
SVN rev 208364 on 2010-05-20 21:07:58Z by nwhitehorn
Fix a long-standing bug in the PowerPC OFW call function on SMP machines
where running ofwdump could cause hangs by forcing all secondary CPUs
into a busy wait with interrupts off during the call.
Following section 8.4 of the Open Firmware PowerPC processor binding,
the firmware is free to overwrite the system interrupt handlers during
OF calls, restoring the OS handlers on exit. On single CPU systems, this
process is invisible to the operating system. On multiple CPU systems,
taking any exception on a secondary CPU while an OF call is in progress
ends with that exception vectored into OF, resulting in a slow movement
of the entire system into firmware context and a machine hang.
MFC after: 3 days
Revision Changes Path
1.29 +64 -5 src/sys/powerpc/aim/ofw_machdep.c
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