Patch "mmc: tmio: Remove bogus un-initialization in tmio_mmc_host_free()" has been added to the 4.0-stable tree

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

mmc: tmio: Remove bogus un-initialization in tmio_mmc_host_free()

to the 4.0-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:
mmc-tmio-remove-bogus-un-initialization-in-tmio_mmc_host_free.patch
and it can be found in the queue-4.0 subdirectory.

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

From: Geert Uytterhoeven <[email protected]>
Date: Wed, 18 Feb 2015 17:34:59 +0100
Subject: mmc: tmio: Remove bogus un-initialization in tmio_mmc_host_free()

From: Geert Uytterhoeven <[email protected]>

commit 13a6a2ed1f5e77ae47c2b1a8e3bf22b2fa2d56ba upstream.

If CONFIG_DEBUG_SLAB=y:

    sh_mobile_sdhi ee100000.sd: Got CD GPIO
    sh_mobile_sdhi ee100000.sd: Got WP GPIO
    platform ee100000.sd: Driver sh_mobile_sdhi requests probe deferral
    ...
    Slab corruption (Not tainted): kmalloc-1024 start=ed8b3c00, len=1024
    2d0: 00 00 00 00 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  ....kkkkkkkkkkkk
    Prev obj: start=ed8b3800, len=1024
    000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
    010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk

Struct tmio_mmc_host is embedded inside struct mmc_host, and thus is freed by the call to mmc_free_host(). Hence it must not be written to afterwards, as that will corrupt freed (and perhaps already reused) memory.

---
 drivers/mmc/host/tmio_mmc_pio.c |    2 --
 1 file changed, 2 deletions(-)

@@ -1073,8 +1073,6 @@ EXPORT_SYMBOL(tmio_mmc_host_alloc);
 void tmio_mmc_host_free(struct tmio_mmc_host *host)
 {
 	mmc_free_host(host->mmc);
-
-	host->mmc = NULL;
 }
 EXPORT_SYMBOL(tmio_mmc_host_free);
 

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

queue-4.0/mmc-tmio-remove-bogus-un-initialization-in-tmio_mmc_host_free.patch