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Archive for August 5th, 2011

timeout overflow in CAM / Drivers under FreeBSD 8.2

without comments

In the process of updating camcontrol to support security features, including the ability to secure erase an SSD to restore performance, I came across and issue where by timeouts passed in via cam layer overflow above 2147 seconds, resulting in instant timeouts.

This is caused by a integer overflow at the driver level when converting the msec timeout value to ticks before passing in to timeout, callout_reset and friends. After discussion on the freebsd-hackers list a fix created by Eygene Ryabinkin and updated by myself to support all drivers has been created.

Download the cam ccb timeout issue patch updated by Eygene Ryabinkin + mps driver support (Updated 22/10/2011)

For more information see the FreeBSD Hackers mailing list archive thread: cam / ata timeout limited to 2147 due to overflow bug?

Written by Dilbert

August 5th, 2011 at 9:57 am

Posted in FreeBSD