Commit 1ddd5049 authored by Bud Brown's avatar Bud Brown Committed by Jens Axboe

cciss: fix lost command issue

Under certain workloads a command may seem to get lost. IOW, the Smart Array
thinks all commands have been completed but we still have commands in our
completion queue. This may lead to system instability, filesystems going
read-only, or even panics depending on the affected filesystem. We add an
extra read to force the write to complete.

Testing shows this extra read avoids the problem.
Signed-off-by: default avatarMike Miller <mike.miller@hp.com>
Cc: stable@kernel.org
Signed-off-by: default avatarJens Axboe <jaxboe@fusionio.com>
parent f0ff1357
...@@ -222,6 +222,7 @@ static void SA5_submit_command( ctlr_info_t *h, CommandList_struct *c) ...@@ -222,6 +222,7 @@ static void SA5_submit_command( ctlr_info_t *h, CommandList_struct *c)
h->ctlr, c->busaddr); h->ctlr, c->busaddr);
#endif /* CCISS_DEBUG */ #endif /* CCISS_DEBUG */
writel(c->busaddr, h->vaddr + SA5_REQUEST_PORT_OFFSET); writel(c->busaddr, h->vaddr + SA5_REQUEST_PORT_OFFSET);
readl(h->vaddr + SA5_REQUEST_PORT_OFFSET);
h->commands_outstanding++; h->commands_outstanding++;
if ( h->commands_outstanding > h->max_outstanding) if ( h->commands_outstanding > h->max_outstanding)
h->max_outstanding = h->commands_outstanding; h->max_outstanding = h->commands_outstanding;
......
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