This is a note to let you know that I've just added the patch titled

    tmio_mmc: don't clear unhandled pending interrupts

to the 2.6.32-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     tmio_mmc-don-t-clear-unhandled-pending-interrupts.patch
and it can be found in the queue-2.6.32 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From b78d6c5f51935ba89df8db33a57bacb547aa7325 Mon Sep 17 00:00:00 2001
From: Yusuke Goda <[email protected]>
Date: Thu, 9 Sep 2010 16:37:39 -0700
Subject: tmio_mmc: don't clear unhandled pending interrupts

From: Yusuke Goda <[email protected]>

commit b78d6c5f51935ba89df8db33a57bacb547aa7325 upstream.

Previously, it was possible for ack_mmc_irqs() to clear pending interrupt
bits in the CTL_STATUS register, even though the interrupt handler had not
been called.  This was because of a race that existed when doing a
read-modify-write sequence on CTL_STATUS.  After the read step in this
sequence, if an interrupt occurred (causing one of the bits in CTL_STATUS
to be set) the write step would inadvertently clear it.

Observed with the TMIO_STAT_RXRDY bit together with CMD53 on AR6002 and
BCM4318 SDIO cards in polled mode.

This patch eliminates this race by only writing to CTL_STATUS and clearing
the interrupts that were passed as an argument to ack_mmc_irqs()."

[[email protected]: rewrote changelog]
Signed-off-by: Yusuke Goda <[email protected]>
Acked-by: Magnus Damm <[email protected]>"
Tested-by: Arnd Hannemann <[email protected]>"
Acked-by: Ian Molton <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Samuel Ortiz <[email protected]>
Cc: Paul Mundt <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/mmc/host/tmio_mmc.h |    5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

--- a/drivers/mmc/host/tmio_mmc.h
+++ b/drivers/mmc/host/tmio_mmc.h
@@ -102,10 +102,7 @@
 
 #define ack_mmc_irqs(host, i) \
        do { \
-               u32 mask;\
-               mask  = sd_ctrl_read32((host), CTL_STATUS); \
-               mask &= ~((i) & TMIO_MASK_IRQ); \
-               sd_ctrl_write32((host), CTL_STATUS, mask); \
+               sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
        } while (0)
 
 


Patches currently in stable-queue which might be from 
[email protected] are

queue-2.6.32/tmio_mmc-don-t-clear-unhandled-pending-interrupts.patch
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