linux-toradex.git/drivers/mtd, branch v4.4.73

mtd: avoid stack overflow in MTD CFI code

2017-05-08T05:46:01+00:00

commit fddcca5107051adf9e4481d2a79ae0616577fd2c upstream.

When map_word gets too large, we use a lot of kernel stack, and for
MTD_MAP_BANK_WIDTH_32, this means we use more than the recommended
1024 bytes in a number of functions:

drivers/mtd/chips/cfi_cmdset_0020.c: In function 'cfi_staa_write_buffers':
drivers/mtd/chips/cfi_cmdset_0020.c:651:1: warning: the frame size of 1336 bytes is larger than 1024 bytes [-Wframe-larger-than=]
drivers/mtd/chips/cfi_cmdset_0020.c: In function 'cfi_staa_erase_varsize':
drivers/mtd/chips/cfi_cmdset_0020.c:972:1: warning: the frame size of 1208 bytes is larger than 1024 bytes [-Wframe-larger-than=]
drivers/mtd/chips/cfi_cmdset_0001.c: In function 'do_write_buffer':
drivers/mtd/chips/cfi_cmdset_0001.c:1835:1: warning: the frame size of 1240 bytes is larger than 1024 bytes [-Wframe-larger-than=]

This can be avoided if all operations on the map word are done
indirectly and the stack gets reused between the calls. We can
mostly achieve this by selecting MTD_COMPLEX_MAPPINGS whenever
MTD_MAP_BANK_WIDTH_32 is set, but for the case that no other
bank width is enabled, we also need to use a non-constant
map_bankwidth() to convince the compiler to use less stack.

Signed-off-by: Arnd Bergmann 
[Brian: this patch mostly achieves its goal by forcing
    MTD_COMPLEX_MAPPINGS (and the accompanying indirection) for 256-bit
    mappings; the rest of the change is mostly a wash, though it helps
    reduce stack size slightly. If we really care about supporting
    256-bit mappings though, we should consider rewriting some of this
    code to avoid keeping and assigning so many 256-bit objects on the
    stack.]
Signed-off-by: Brian Norris 
Signed-off-by: Greg Kroah-Hartman

ubi/upd: Always flush after prepared for an update

2017-04-27T07:09:33+00:00

commit 9cd9a21ce070be8a918ffd3381468315a7a76ba6 upstream.

In commit 6afaf8a484cb ("UBI: flush wl before clearing update marker") I
managed to trigger and fix a similar bug. Now here is another version of
which I assumed it wouldn't matter back then but it turns out UBI has a
check for it and will error out like this:

|ubi0 warning: validate_vid_hdr: inconsistent used_ebs
|ubi0 error: validate_vid_hdr: inconsistent VID header at PEB 592

All you need to trigger this is? "ubiupdatevol /dev/ubi0_0 file" + a
powercut in the middle of the operation.
ubi_start_update() sets the update-marker and puts all EBs on the erase
list. After that userland can proceed to write new data while the old EB
aren't erased completely. A powercut at this point is usually not that
much of a tragedy. UBI won't give read access to the static volume
because it has the update marker. It will most likely set the corrupted
flag because it misses some EBs.
So we are all good. Unless the size of the image that has been written
differs from the old image in the magnitude of at least one EB. In that
case UBI will find two different values for `used_ebs' and refuse to
attach the image with the error message mentioned above.

So in order not to get in the situation, the patch will ensure that we
wait until everything is removed before it tries to write any data.
The alternative would be to detect such a case and remove all EBs at the
attached time after we processed the volume-table and see the
update-marker set. The patch looks bigger and I doubt it is worth it
since usually the write() will wait from time to time for a new EB since
usually there not that many spare EB that can be used.

Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Richard Weinberger 
Signed-off-by: Greg Kroah-Hartman

mtd: bcm47xxpart: fix parsing first block after aligned TRX

2017-04-18T05:14:35+00:00

commit bd5d21310133921021d78995ad6346f908483124 upstream.

After parsing TRX we should skip to the first block placed behind it.
Our code was working only with TRX with length not aligned to the
blocksize. In other cases (length aligned) it was missing the block
places right after TRX.

This fixes calculation and simplifies the comment.

Signed-off-by: Rafał Miłecki 
Signed-off-by: Brian Norris 
Signed-off-by: Amit Pundir 
Signed-off-by: Greg Kroah-Hartman

mtd: pmcmsp: use kstrndup instead of kmalloc+strncpy

2017-03-18T11:09:56+00:00

commit 906b268477bc03daaa04f739844c120fe4dbc991 upstream.

kernelci.org reports a warning for this driver, as it copies a local
variable into a 'const char *' string:

    drivers/mtd/maps/pmcmsp-flash.c:149:30: warning: passing argument 1 of 'strncpy' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]

Using kstrndup() simplifies the code and avoids the warning.

Signed-off-by: Arnd Bergmann 
Acked-by: Marek Vasut 
Signed-off-by: Brian Norris 
Signed-off-by: Greg Kroah-Hartman

mtd: nand: xway: disable module support

2017-01-26T07:23:48+00:00

commit 73529c872a189c747bdb528ce9b85b67b0e28dec upstream.

The xway_nand driver accesses the ltq_ebu_membase symbol which is not
exported. This also should not get exported and we should handle the
EBU interface in a better way later. This quick fix just deactivated
support for building as module.

Fixes: 99f2b107924c ("mtd: lantiq: Add NAND support on Lantiq XWAY SoC.")
Signed-off-by: Hauke Mehrtens 
Signed-off-by: Boris Brezillon 
Signed-off-by: Greg Kroah-Hartman

ubi: fastmap: Fix add_vol() return value test in ubi_attach_fastmap()

2016-11-10T15:36:37+00:00

commit 40b6e61ac72e99672e47cdb99c8d7d226004169b upstream.

Commit e96a8a3bb671 ("UBI: Fastmap: Do not add vol if it already
exists") introduced a bug by changing the possible error codes returned
by add_vol():
- this function no longer returns NULL in case of allocation failure
  but return ERR_PTR(-ENOMEM)
- when a duplicate entry in the volume RB tree is found it returns
  ERR_PTR(-EEXIST) instead of ERR_PTR(-EINVAL)

Fix the tests done on add_vol() return val to match this new behavior.

Fixes: e96a8a3bb671 ("UBI: Fastmap: Do not add vol if it already exists")
Reported-by: Dan Carpenter 
Signed-off-by: Boris Brezillon 
Acked-by: Sheng Yong 
Signed-off-by: Richard Weinberger 
Signed-off-by: Greg Kroah-Hartman

UBI: fastmap: scrub PEB when bitflips are detected in a free PEB EC header

2016-11-10T15:36:36+00:00

commit ecbfa8eabae9cd73522d1d3d15869703c263d859 upstream.

scan_pool() does not mark the PEB for scrubing when bitflips are
detected in the EC header of a free PEB (VID header region left to
0xff).
Make sure we scrub the PEB in this case.

Signed-off-by: Boris Brezillon 
Fixes: dbb7d2a88d2a ("UBI: Add fastmap core")
Signed-off-by: Richard Weinberger 
Signed-off-by: Greg Kroah-Hartman

ubi: Deal with interrupted erasures in WL

2016-10-28T07:01:28+00:00

commit 2365418879e9abf12ea9def7f9f3caf0dfa7ffb0 upstream.

When Fastmap is used we can face here an -EBADMSG
since Fastmap cannot know about unmaps.
If the erasure was interrupted the PEB may show ECC
errors and UBI would go to ro-mode as it assumes
that the PEB was check during attach time, which is
not the case with Fastmap.

Fixes: dbb7d2a88d ("UBI: Add fastmap core")
Signed-off-by: Richard Weinberger 
Signed-off-by: Greg Kroah-Hartman

mtd: nand: davinci: Reinitialize the HW ECC engine in 4bit hwctl

2016-10-07T13:23:40+00:00

commit f6d7c1b5598b6407c3f1da795dd54acf99c1990c upstream.

This fixes subpage writes when using 4-bit HW ECC.

There has been numerous reports about ECC errors with devices using this
driver for a while.  Also the 4-bit ECC has been reported as broken with
subpages in [1] and with 16 bits NANDs in the driver and in mach* board
files both in mainline and in the vendor BSPs.

What I saw with 4-bit ECC on a 16bits NAND (on an LCDK) which got me to
try reinitializing the ECC engine:
- R/W on whole pages properly generates/checks RS code
- try writing the 1st subpage only of a blank page, the subpage is well
  written and the RS code properly generated, re-reading the same page
  the HW detects some ECC error, reading the same page again no ECC
  error is detected

Note that the ECC engine is already reinitialized in the 1-bit case.

Tested on my LCDK with UBI+UBIFS using subpages.
This could potentially get rid of the issue workarounded in [1].

[1] 28c015a9daab ("mtd: davinci-nand: disable subpage write for keystone-nand")

Fixes: 6a4123e581b3 ("mtd: nand: davinci_nand, 4-bit ECC for smallpage")
Signed-off-by: Karl Beldan 
Acked-by: Boris Brezillon 
Signed-off-by: Brian Norris 
Signed-off-by: Greg Kroah-Hartman

mtd: pmcmsp-flash: Allocating too much in init_msp_flash()

2016-09-30T08:18:37+00:00

commit 79ad07d45743721010e766e65dc004ad249bd429 upstream.

There is a cut and paste issue here.  The bug is that we are allocating
more memory than necessary for msp_maps.  We should be allocating enough
space for a map_info struct (144 bytes) but we instead allocate enough
for an mtd_info struct (1840 bytes).  It's a small waste.

The other part of this is not harmful but when we allocated msp_flash
then we allocated enough space fro a map_info pointer instead of an
mtd_info pointer.  But since pointers are the same size it works out
fine.

Anyway, I decided to clean up all three allocations a bit to make them
a bit more consistent and clear.

Fixes: 68aa0fa87f6d ('[MTD] PMC MSP71xx flash/rootfs mappings')
Signed-off-by: Dan Carpenter 
Signed-off-by: Brian Norris 
Signed-off-by: Greg Kroah-Hartman