https://github.com/torvalds/linux
Revision c0af2c057d7ce3f0b260f9380d187a82bb5cab28 authored by Mike Marciniszyn on 16 February 2011, 15:48:25 UTC, committed by Roland Dreier on 17 February 2011, 22:04:50 UTC
There is a double completion associated with error handling for RC QPs.

The sequence is:

 - The do_rc_ack() routine fields an RNR nack and there are 0
   rnr_retries configured on the QP.
 - qib_error_qp() stops the pending timer
 - qib_rc_send_complete() is called from sdma_complete()
 - qib_rc_send_complete() starts the timer because the msb of the psn
   just completed says an ack is needed.
 - a bunch of flushes occur as ipoib posts WQEs to an error'ed QP
 - rc_timeout() calls qib_restart_rc()
 - qib_restart_rc() calls qib_send_complete() with a
   IB_WC_RETRY_EXC_ERR on a wqe that has already been completed in the
   past

The fix avoids starting the timer since another packet will never
arrive.

Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
1 parent 414ed90
Raw File
Tip revision: c0af2c057d7ce3f0b260f9380d187a82bb5cab28 authored by Mike Marciniszyn on 16 February 2011, 15:48:25 UTC
IB/qib: Prevent double completions after a timeout or RNR error
Tip revision: c0af2c0
REPORTING-BUGS
[Some of this is taken from Frohwalt Egerer's original linux-kernel FAQ]

     What follows is a suggested procedure for reporting Linux bugs. You
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     If the failure includes an "OOPS:" type message in your log or on
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      Send the output to the maintainer of the kernel area that seems to
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If it occurs repeatably try and describe how to recreate it. That is
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      First run the ver_linux script included as scripts/ver_linux, which
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Use that information to fill in all fields of the bug report form, and
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[4.] Kernel information
[4.1.] Kernel version (from /proc/version):
[4.2.] Kernel .config file:
[5.] Most recent kernel version which did not have the bug:
[6.] Output of Oops.. message (if applicable) with symbolic information
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[7.] A small shell script or example program which triggers the
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[8.3.] Module information (from /proc/modules):
[8.4.] Loaded driver and hardware information (/proc/ioports, /proc/iomem)
[8.5.] PCI information ('lspci -vvv' as root)
[8.6.] SCSI information (from /proc/scsi/scsi)
[8.7.] Other information that might be relevant to the problem
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