<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/mtd, branch v3.2.68</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>UBI: Fix invalid vfree()</title>
<updated>2015-02-20T00:49:24+00:00</updated>
<author>
<name>Richard Weinberger</name>
<email>richard@nod.at</email>
</author>
<published>2014-10-26T23:46:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=83e1f5831dc8fb25704bba388c5cd0e8780e5fff'/>
<id>83e1f5831dc8fb25704bba388c5cd0e8780e5fff</id>
<content type='text'>
commit f38aed975c0c3645bbdfc5ebe35726e64caaf588 upstream.

The logic of vfree()'ing vol-&gt;upd_buf is tied to vol-&gt;updating.
In ubi_start_update() vol-&gt;updating is set long before vmalloc()'ing
vol-&gt;upd_buf. If we encounter a write failure in ubi_start_update()
before vmalloc() the UBI device release function will try to vfree()
vol-&gt;upd_buf because vol-&gt;updating is set.
Fix this by allocating vol-&gt;upd_buf directly after setting vol-&gt;updating.

Fixes:
[   31.559338] UBI warning: vol_cdev_release: update of volume 2 not finished, volume is damaged
[   31.559340] ------------[ cut here ]------------
[   31.559343] WARNING: CPU: 1 PID: 2747 at mm/vmalloc.c:1446 __vunmap+0xe3/0x110()
[   31.559344] Trying to vfree() nonexistent vm area (ffffc90001f2b000)
[   31.559345] Modules linked in:
[   31.565620]  0000000000000bba ffff88002a0cbdb0 ffffffff818f0497 ffff88003b9ba148
[   31.566347]  ffff88002a0cbde0 ffffffff8156f515 ffff88003b9ba148 0000000000000bba
[   31.567073]  0000000000000000 0000000000000000 ffff88002a0cbe88 ffffffff8156c10a
[   31.567793] Call Trace:
[   31.568034]  [&lt;ffffffff818f0497&gt;] dump_stack+0x4e/0x7a
[   31.568510]  [&lt;ffffffff8156f515&gt;] ubi_io_write_vid_hdr+0x155/0x160
[   31.569084]  [&lt;ffffffff8156c10a&gt;] ubi_eba_write_leb+0x23a/0x870
[   31.569628]  [&lt;ffffffff81569b36&gt;] vol_cdev_write+0x226/0x380
[   31.570155]  [&lt;ffffffff81179265&gt;] vfs_write+0xb5/0x1f0
[   31.570627]  [&lt;ffffffff81179f8a&gt;] SyS_pwrite64+0x6a/0xa0
[   31.571123]  [&lt;ffffffff818fde12&gt;] system_call_fastpath+0x16/0x1b

Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Artem Bityutskiy &lt;artem.bityutskiy@linux.intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f38aed975c0c3645bbdfc5ebe35726e64caaf588 upstream.

The logic of vfree()'ing vol-&gt;upd_buf is tied to vol-&gt;updating.
In ubi_start_update() vol-&gt;updating is set long before vmalloc()'ing
vol-&gt;upd_buf. If we encounter a write failure in ubi_start_update()
before vmalloc() the UBI device release function will try to vfree()
vol-&gt;upd_buf because vol-&gt;updating is set.
Fix this by allocating vol-&gt;upd_buf directly after setting vol-&gt;updating.

Fixes:
[   31.559338] UBI warning: vol_cdev_release: update of volume 2 not finished, volume is damaged
[   31.559340] ------------[ cut here ]------------
[   31.559343] WARNING: CPU: 1 PID: 2747 at mm/vmalloc.c:1446 __vunmap+0xe3/0x110()
[   31.559344] Trying to vfree() nonexistent vm area (ffffc90001f2b000)
[   31.559345] Modules linked in:
[   31.565620]  0000000000000bba ffff88002a0cbdb0 ffffffff818f0497 ffff88003b9ba148
[   31.566347]  ffff88002a0cbde0 ffffffff8156f515 ffff88003b9ba148 0000000000000bba
[   31.567073]  0000000000000000 0000000000000000 ffff88002a0cbe88 ffffffff8156c10a
[   31.567793] Call Trace:
[   31.568034]  [&lt;ffffffff818f0497&gt;] dump_stack+0x4e/0x7a
[   31.568510]  [&lt;ffffffff8156f515&gt;] ubi_io_write_vid_hdr+0x155/0x160
[   31.569084]  [&lt;ffffffff8156c10a&gt;] ubi_eba_write_leb+0x23a/0x870
[   31.569628]  [&lt;ffffffff81569b36&gt;] vol_cdev_write+0x226/0x380
[   31.570155]  [&lt;ffffffff81179265&gt;] vfs_write+0xb5/0x1f0
[   31.570627]  [&lt;ffffffff81179f8a&gt;] SyS_pwrite64+0x6a/0xa0
[   31.571123]  [&lt;ffffffff818fde12&gt;] system_call_fastpath+0x16/0x1b

Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
Signed-off-by: Artem Bityutskiy &lt;artem.bityutskiy@linux.intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd/ftl: fix the double free of the buffers allocated in build_maps()</title>
<updated>2014-09-13T22:41:38+00:00</updated>
<author>
<name>Kevin Hao</name>
<email>haokexin@gmail.com</email>
</author>
<published>2014-07-03T02:35:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6b59836ff262fb46a29b5a3aecea82c69d0a9401'/>
<id>6b59836ff262fb46a29b5a3aecea82c69d0a9401</id>
<content type='text'>
commit a152056c912db82860a8b4c23d0bd3a5aa89e363 upstream.

I got the following panic on my fsl p5020ds board.

  Unable to handle kernel paging request for data at address 0x7375627379737465
  Faulting instruction address: 0xc000000000100778
  Oops: Kernel access of bad area, sig: 11 [#1]
  SMP NR_CPUS=24 CoreNet Generic
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.15.0-next-20140613 #145
  task: c0000000fe080000 ti: c0000000fe088000 task.ti: c0000000fe088000
  NIP: c000000000100778 LR: c00000000010073c CTR: 0000000000000000
  REGS: c0000000fe08aa00 TRAP: 0300   Not tainted  (3.15.0-next-20140613)
  MSR: 0000000080029000 &lt;CE,EE,ME&gt;  CR: 24ad2e24  XER: 00000000
  DEAR: 7375627379737465 ESR: 0000000000000000 SOFTE: 1
  GPR00: c0000000000c99b0 c0000000fe08ac80 c0000000009598e0 c0000000fe001d80
  GPR04: 00000000000000d0 0000000000000913 c000000007902b20 0000000000000000
  GPR08: c0000000feaae888 0000000000000000 0000000007091000 0000000000200200
  GPR12: 0000000028ad2e28 c00000000fff4000 c0000000007abe08 0000000000000000
  GPR16: c0000000007ab160 c0000000007aaf98 c00000000060ba68 c0000000007abda8
  GPR20: c0000000007abde8 c0000000feaea6f8 c0000000feaea708 c0000000007abd10
  GPR24: c000000000989370 c0000000008c6228 00000000000041ed c0000000fe00a400
  GPR28: c00000000017c1cc 00000000000000d0 7375627379737465 c0000000fe001d80
  NIP [c000000000100778] .__kmalloc_track_caller+0x70/0x168
  LR [c00000000010073c] .__kmalloc_track_caller+0x34/0x168
  Call Trace:
  [c0000000fe08ac80] [c00000000087e6b8] uevent_sock_list+0x0/0x10 (unreliable)
  [c0000000fe08ad20] [c0000000000c99b0] .kstrdup+0x44/0x90
  [c0000000fe08adc0] [c00000000017c1cc] .__kernfs_new_node+0x4c/0x130
  [c0000000fe08ae70] [c00000000017d7e4] .kernfs_new_node+0x2c/0x64
  [c0000000fe08aef0] [c00000000017db00] .kernfs_create_dir_ns+0x34/0xc8
  [c0000000fe08af80] [c00000000018067c] .sysfs_create_dir_ns+0x58/0xcc
  [c0000000fe08b010] [c0000000002c711c] .kobject_add_internal+0xc8/0x384
  [c0000000fe08b0b0] [c0000000002c7644] .kobject_add+0x64/0xc8
  [c0000000fe08b140] [c000000000355ebc] .device_add+0x11c/0x654
  [c0000000fe08b200] [c0000000002b5988] .add_disk+0x20c/0x4b4
  [c0000000fe08b2c0] [c0000000003a21d4] .add_mtd_blktrans_dev+0x340/0x514
  [c0000000fe08b350] [c0000000003a3410] .mtdblock_add_mtd+0x74/0xb4
  [c0000000fe08b3e0] [c0000000003a32cc] .blktrans_notify_add+0x64/0x94
  [c0000000fe08b470] [c00000000039b5b4] .add_mtd_device+0x1d4/0x368
  [c0000000fe08b520] [c00000000039b830] .mtd_device_parse_register+0xe8/0x104
  [c0000000fe08b5c0] [c0000000003b8408] .of_flash_probe+0x72c/0x734
  [c0000000fe08b750] [c00000000035ba40] .platform_drv_probe+0x38/0x84
  [c0000000fe08b7d0] [c0000000003599a4] .really_probe+0xa4/0x29c
  [c0000000fe08b870] [c000000000359d3c] .__driver_attach+0x100/0x104
  [c0000000fe08b900] [c00000000035746c] .bus_for_each_dev+0x84/0xe4
  [c0000000fe08b9a0] [c0000000003593c0] .driver_attach+0x24/0x38
  [c0000000fe08ba10] [c000000000358f24] .bus_add_driver+0x1c8/0x2ac
  [c0000000fe08bab0] [c00000000035a3a4] .driver_register+0x8c/0x158
  [c0000000fe08bb30] [c00000000035b9f4] .__platform_driver_register+0x6c/0x80
  [c0000000fe08bba0] [c00000000084e080] .of_flash_driver_init+0x1c/0x30
  [c0000000fe08bc10] [c000000000001864] .do_one_initcall+0xbc/0x238
  [c0000000fe08bd00] [c00000000082cdc0] .kernel_init_freeable+0x188/0x268
  [c0000000fe08bdb0] [c0000000000020a0] .kernel_init+0x1c/0xf7c
  [c0000000fe08be30] [c000000000000884] .ret_from_kernel_thread+0x58/0xd4
  Instruction dump:
  41bd0010 480000c8 4bf04eb5 60000000 e94d0028 e93f0000 7cc95214 e8a60008
  7fc9502a 2fbe0000 419e00c8 e93f0022 &lt;7f7e482a&gt; 39200000 88ed06b2 992d06b2
  ---[ end trace b4c9a94804a42d40 ]---

It seems that the corrupted partition header on my mtd device triggers
a bug in the ftl. In function build_maps() it will allocate the buffers
needed by the mtd partition, but if something goes wrong such as kmalloc
failure, mtd read error or invalid partition header parameter, it will
free all allocated buffers and then return non-zero. In my case, it
seems that partition header parameter 'NumTransferUnits' is invalid.

And the ftl_freepart() is a function which free all the partition
buffers allocated by build_maps(). Given the build_maps() is a self
cleaning function, so there is no need to invoke this function even
if build_maps() return with error. Otherwise it will causes the
buffers to be freed twice and then weird things would happen.

Signed-off-by: Kevin Hao &lt;haokexin@gmail.com&gt;
Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a152056c912db82860a8b4c23d0bd3a5aa89e363 upstream.

I got the following panic on my fsl p5020ds board.

  Unable to handle kernel paging request for data at address 0x7375627379737465
  Faulting instruction address: 0xc000000000100778
  Oops: Kernel access of bad area, sig: 11 [#1]
  SMP NR_CPUS=24 CoreNet Generic
  Modules linked in:
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.15.0-next-20140613 #145
  task: c0000000fe080000 ti: c0000000fe088000 task.ti: c0000000fe088000
  NIP: c000000000100778 LR: c00000000010073c CTR: 0000000000000000
  REGS: c0000000fe08aa00 TRAP: 0300   Not tainted  (3.15.0-next-20140613)
  MSR: 0000000080029000 &lt;CE,EE,ME&gt;  CR: 24ad2e24  XER: 00000000
  DEAR: 7375627379737465 ESR: 0000000000000000 SOFTE: 1
  GPR00: c0000000000c99b0 c0000000fe08ac80 c0000000009598e0 c0000000fe001d80
  GPR04: 00000000000000d0 0000000000000913 c000000007902b20 0000000000000000
  GPR08: c0000000feaae888 0000000000000000 0000000007091000 0000000000200200
  GPR12: 0000000028ad2e28 c00000000fff4000 c0000000007abe08 0000000000000000
  GPR16: c0000000007ab160 c0000000007aaf98 c00000000060ba68 c0000000007abda8
  GPR20: c0000000007abde8 c0000000feaea6f8 c0000000feaea708 c0000000007abd10
  GPR24: c000000000989370 c0000000008c6228 00000000000041ed c0000000fe00a400
  GPR28: c00000000017c1cc 00000000000000d0 7375627379737465 c0000000fe001d80
  NIP [c000000000100778] .__kmalloc_track_caller+0x70/0x168
  LR [c00000000010073c] .__kmalloc_track_caller+0x34/0x168
  Call Trace:
  [c0000000fe08ac80] [c00000000087e6b8] uevent_sock_list+0x0/0x10 (unreliable)
  [c0000000fe08ad20] [c0000000000c99b0] .kstrdup+0x44/0x90
  [c0000000fe08adc0] [c00000000017c1cc] .__kernfs_new_node+0x4c/0x130
  [c0000000fe08ae70] [c00000000017d7e4] .kernfs_new_node+0x2c/0x64
  [c0000000fe08aef0] [c00000000017db00] .kernfs_create_dir_ns+0x34/0xc8
  [c0000000fe08af80] [c00000000018067c] .sysfs_create_dir_ns+0x58/0xcc
  [c0000000fe08b010] [c0000000002c711c] .kobject_add_internal+0xc8/0x384
  [c0000000fe08b0b0] [c0000000002c7644] .kobject_add+0x64/0xc8
  [c0000000fe08b140] [c000000000355ebc] .device_add+0x11c/0x654
  [c0000000fe08b200] [c0000000002b5988] .add_disk+0x20c/0x4b4
  [c0000000fe08b2c0] [c0000000003a21d4] .add_mtd_blktrans_dev+0x340/0x514
  [c0000000fe08b350] [c0000000003a3410] .mtdblock_add_mtd+0x74/0xb4
  [c0000000fe08b3e0] [c0000000003a32cc] .blktrans_notify_add+0x64/0x94
  [c0000000fe08b470] [c00000000039b5b4] .add_mtd_device+0x1d4/0x368
  [c0000000fe08b520] [c00000000039b830] .mtd_device_parse_register+0xe8/0x104
  [c0000000fe08b5c0] [c0000000003b8408] .of_flash_probe+0x72c/0x734
  [c0000000fe08b750] [c00000000035ba40] .platform_drv_probe+0x38/0x84
  [c0000000fe08b7d0] [c0000000003599a4] .really_probe+0xa4/0x29c
  [c0000000fe08b870] [c000000000359d3c] .__driver_attach+0x100/0x104
  [c0000000fe08b900] [c00000000035746c] .bus_for_each_dev+0x84/0xe4
  [c0000000fe08b9a0] [c0000000003593c0] .driver_attach+0x24/0x38
  [c0000000fe08ba10] [c000000000358f24] .bus_add_driver+0x1c8/0x2ac
  [c0000000fe08bab0] [c00000000035a3a4] .driver_register+0x8c/0x158
  [c0000000fe08bb30] [c00000000035b9f4] .__platform_driver_register+0x6c/0x80
  [c0000000fe08bba0] [c00000000084e080] .of_flash_driver_init+0x1c/0x30
  [c0000000fe08bc10] [c000000000001864] .do_one_initcall+0xbc/0x238
  [c0000000fe08bd00] [c00000000082cdc0] .kernel_init_freeable+0x188/0x268
  [c0000000fe08bdb0] [c0000000000020a0] .kernel_init+0x1c/0xf7c
  [c0000000fe08be30] [c000000000000884] .ret_from_kernel_thread+0x58/0xd4
  Instruction dump:
  41bd0010 480000c8 4bf04eb5 60000000 e94d0028 e93f0000 7cc95214 e8a60008
  7fc9502a 2fbe0000 419e00c8 e93f0022 &lt;7f7e482a&gt; 39200000 88ed06b2 992d06b2
  ---[ end trace b4c9a94804a42d40 ]---

It seems that the corrupted partition header on my mtd device triggers
a bug in the ftl. In function build_maps() it will allocate the buffers
needed by the mtd partition, but if something goes wrong such as kmalloc
failure, mtd read error or invalid partition header parameter, it will
free all allocated buffers and then return non-zero. In my case, it
seems that partition header parameter 'NumTransferUnits' is invalid.

And the ftl_freepart() is a function which free all the partition
buffers allocated by build_maps(). Given the build_maps() is a self
cleaning function, so there is no need to invoke this function even
if build_maps() return with error. Otherwise it will causes the
buffers to be freed twice and then weird things would happen.

Signed-off-by: Kevin Hao &lt;haokexin@gmail.com&gt;
Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: mxc_nand: remove duplicated ecc_stats counting</title>
<updated>2014-04-01T23:58:40+00:00</updated>
<author>
<name>Michael Grzeschik</name>
<email>m.grzeschik@pengutronix.de</email>
</author>
<published>2013-11-29T13:14:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a0809936e2ad052ef0fbdba0e258bfaf0c0dc9bc'/>
<id>a0809936e2ad052ef0fbdba0e258bfaf0c0dc9bc</id>
<content type='text'>
commit 0566477762f9e174e97af347ee9c865f908a5647 upstream.

The ecc_stats.corrected count variable will already be incremented in
the above framework-layer just after this callback.

Signed-off-by: Michael Grzeschik &lt;m.grzeschik@pengutronix.de&gt;
Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 0566477762f9e174e97af347ee9c865f908a5647 upstream.

The ecc_stats.corrected count variable will already be incremented in
the above framework-layer just after this callback.

Signed-off-by: Michael Grzeschik &lt;m.grzeschik@pengutronix.de&gt;
Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: gpmi: fix kernel BUG due to racing DMA operations</title>
<updated>2014-01-03T04:33:20+00:00</updated>
<author>
<name>Huang Shijie</name>
<email>b32955@freescale.com</email>
</author>
<published>2013-11-11T04:13:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=425b0e67595dcbc20bc5b1a2a92ad0965754629c'/>
<id>425b0e67595dcbc20bc5b1a2a92ad0965754629c</id>
<content type='text'>
commit 7b3d2fb92067bcb29f0f085a9fa9fa64920a6646 upstream.

[1] The gpmi uses the nand_command_lp to issue the commands to NAND chips.
    The gpmi issues a DMA operation with gpmi_cmd_ctrl when it handles
    a NAND_CMD_NONE control command. So when we read a page(NAND_CMD_READ0)
    from the NAND, we may send two DMA operations back-to-back.

    If we do not serialize the two DMA operations, we will meet a bug when

    1.1) we enable CONFIG_DMA_API_DEBUG, CONFIG_DMADEVICES_DEBUG,
         and CONFIG_DEBUG_SG.

    1.2) Use the following commands in an UART console and a SSH console:
         cmd 1: while true;do dd if=/dev/mtd0 of=/dev/null;done
         cmd 1: while true;do dd if=/dev/mmcblk0 of=/dev/null;done

    The kernel log shows below:
    -----------------------------------------------------------------
    kernel BUG at lib/scatterlist.c:28!
    Unable to handle kernel NULL pointer dereference at virtual address 00000000
      .........................
    [&lt;80044a0c&gt;] (__bug+0x18/0x24) from [&lt;80249b74&gt;] (sg_next+0x48/0x4c)
    [&lt;80249b74&gt;] (sg_next+0x48/0x4c) from [&lt;80255398&gt;] (debug_dma_unmap_sg+0x170/0x1a4)
    [&lt;80255398&gt;] (debug_dma_unmap_sg+0x170/0x1a4) from [&lt;8004af58&gt;] (dma_unmap_sg+0x14/0x6c)
    [&lt;8004af58&gt;] (dma_unmap_sg+0x14/0x6c) from [&lt;8027e594&gt;] (mxs_dma_tasklet+0x18/0x1c)
    [&lt;8027e594&gt;] (mxs_dma_tasklet+0x18/0x1c) from [&lt;8007d444&gt;] (tasklet_action+0x114/0x164)
    -----------------------------------------------------------------

    1.3) Assume the two DMA operations is X (first) and Y (second).

         The root cause of the bug:
	   Assume process P issues DMA X, and sleep on the completion
	 @this-&gt;dma_done. X's tasklet callback is dma_irq_callback. It firstly
	 wake up the process sleeping on the completion @this-&gt;dma_done,
	 and then trid to unmap the scatterlist S. The waked process P will
	 issue Y in another ARM core. Y initializes S-&gt;sg_magic to zero
	 with sg_init_one(), while dma_irq_callback is unmapping S at the same
	 time.

	 See the diagram:

                   ARM core 0              |         ARM core 1
	 -------------------------------------------------------------
         (P issues DMA X, then sleep)  --&gt; |
                                           |
         (X's tasklet wakes P)         --&gt; |
                                           |
                                           | &lt;-- (P begin to issue DMA Y)
                                           |
         (X's tasklet unmap the            |
      scatterlist S with dma_unmap_sg) --&gt; | &lt;-- (Y calls sg_init_one() to init
                                           |      scatterlist S)
                                           |

[2] This patch serialize both the X and Y in the following way:
     Unmap the DMA scatterlist S firstly, and wake up the process at the end
     of the DMA callback, in such a way, Y will be executed after X.

     After this patch:

                   ARM core 0              |         ARM core 1
	 -------------------------------------------------------------
         (P issues DMA X, then sleep)  --&gt; |
                                           |
         (X's tasklet unmap the            |
      scatterlist S with dma_unmap_sg) --&gt; |
                                           |
         (X's tasklet wakes P)         --&gt; |
                                           |
                                           | &lt;-- (P begin to issue DMA Y)
                                           |
                                           | &lt;-- (Y calls sg_init_one() to init
                                           |     scatterlist S)
                                           |

Signed-off-by: Huang Shijie &lt;b32955@freescale.com&gt;
Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 7b3d2fb92067bcb29f0f085a9fa9fa64920a6646 upstream.

[1] The gpmi uses the nand_command_lp to issue the commands to NAND chips.
    The gpmi issues a DMA operation with gpmi_cmd_ctrl when it handles
    a NAND_CMD_NONE control command. So when we read a page(NAND_CMD_READ0)
    from the NAND, we may send two DMA operations back-to-back.

    If we do not serialize the two DMA operations, we will meet a bug when

    1.1) we enable CONFIG_DMA_API_DEBUG, CONFIG_DMADEVICES_DEBUG,
         and CONFIG_DEBUG_SG.

    1.2) Use the following commands in an UART console and a SSH console:
         cmd 1: while true;do dd if=/dev/mtd0 of=/dev/null;done
         cmd 1: while true;do dd if=/dev/mmcblk0 of=/dev/null;done

    The kernel log shows below:
    -----------------------------------------------------------------
    kernel BUG at lib/scatterlist.c:28!
    Unable to handle kernel NULL pointer dereference at virtual address 00000000
      .........................
    [&lt;80044a0c&gt;] (__bug+0x18/0x24) from [&lt;80249b74&gt;] (sg_next+0x48/0x4c)
    [&lt;80249b74&gt;] (sg_next+0x48/0x4c) from [&lt;80255398&gt;] (debug_dma_unmap_sg+0x170/0x1a4)
    [&lt;80255398&gt;] (debug_dma_unmap_sg+0x170/0x1a4) from [&lt;8004af58&gt;] (dma_unmap_sg+0x14/0x6c)
    [&lt;8004af58&gt;] (dma_unmap_sg+0x14/0x6c) from [&lt;8027e594&gt;] (mxs_dma_tasklet+0x18/0x1c)
    [&lt;8027e594&gt;] (mxs_dma_tasklet+0x18/0x1c) from [&lt;8007d444&gt;] (tasklet_action+0x114/0x164)
    -----------------------------------------------------------------

    1.3) Assume the two DMA operations is X (first) and Y (second).

         The root cause of the bug:
	   Assume process P issues DMA X, and sleep on the completion
	 @this-&gt;dma_done. X's tasklet callback is dma_irq_callback. It firstly
	 wake up the process sleeping on the completion @this-&gt;dma_done,
	 and then trid to unmap the scatterlist S. The waked process P will
	 issue Y in another ARM core. Y initializes S-&gt;sg_magic to zero
	 with sg_init_one(), while dma_irq_callback is unmapping S at the same
	 time.

	 See the diagram:

                   ARM core 0              |         ARM core 1
	 -------------------------------------------------------------
         (P issues DMA X, then sleep)  --&gt; |
                                           |
         (X's tasklet wakes P)         --&gt; |
                                           |
                                           | &lt;-- (P begin to issue DMA Y)
                                           |
         (X's tasklet unmap the            |
      scatterlist S with dma_unmap_sg) --&gt; | &lt;-- (Y calls sg_init_one() to init
                                           |      scatterlist S)
                                           |

[2] This patch serialize both the X and Y in the following way:
     Unmap the DMA scatterlist S firstly, and wake up the process at the end
     of the DMA callback, in such a way, Y will be executed after X.

     After this patch:

                   ARM core 0              |         ARM core 1
	 -------------------------------------------------------------
         (P issues DMA X, then sleep)  --&gt; |
                                           |
         (X's tasklet unmap the            |
      scatterlist S with dma_unmap_sg) --&gt; |
                                           |
         (X's tasklet wakes P)         --&gt; |
                                           |
                                           | &lt;-- (P begin to issue DMA Y)
                                           |
                                           | &lt;-- (Y calls sg_init_one() to init
                                           |     scatterlist S)
                                           |

Signed-off-by: Huang Shijie &lt;b32955@freescale.com&gt;
Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: m25p80: fix allocation size</title>
<updated>2014-01-03T04:33:18+00:00</updated>
<author>
<name>Brian Norris</name>
<email>computersforpeace@gmail.com</email>
</author>
<published>2013-07-25T01:32:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2a4c85e77b4bd77a83382f74c99da1c388a0fab2'/>
<id>2a4c85e77b4bd77a83382f74c99da1c388a0fab2</id>
<content type='text'>
commit 778d226a1462572b51d6777cdb1d611543410cb4 upstream.

This patch fixes two memory errors:

1. During a probe failure (in mtd_device_parse_register?) the command
   buffer would not be freed.

2. The command buffer's size is determined based on the 'fast_read'
   boolean, but the assignment of fast_read is made after this
   allocation. Thus, the buffer may be allocated "too small".

To fix the first, just switch to the devres version of kzalloc.

To fix the second, increase MAX_CMD_SIZE unconditionally. It's not worth
saving a byte to fiddle around with the conditions here.

This problem was reported by Yuhang Wang a while back.

Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
Reported-by: Yuhang Wang &lt;wangyuhang2014@gmail.com&gt;
Reviewed-by: Sourav Poddar &lt;sourav.poddar@ti.com&gt;
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 778d226a1462572b51d6777cdb1d611543410cb4 upstream.

This patch fixes two memory errors:

1. During a probe failure (in mtd_device_parse_register?) the command
   buffer would not be freed.

2. The command buffer's size is determined based on the 'fast_read'
   boolean, but the assignment of fast_read is made after this
   allocation. Thus, the buffer may be allocated "too small".

To fix the first, just switch to the devres version of kzalloc.

To fix the second, increase MAX_CMD_SIZE unconditionally. It's not worth
saving a byte to fiddle around with the conditions here.

This problem was reported by Yuhang Wang a while back.

Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
Reported-by: Yuhang Wang &lt;wangyuhang2014@gmail.com&gt;
Reviewed-by: Sourav Poddar &lt;sourav.poddar@ti.com&gt;
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: nand: hack ONFI for non-power-of-2 dimensions</title>
<updated>2014-01-03T04:33:18+00:00</updated>
<author>
<name>Brian Norris</name>
<email>computersforpeace@gmail.com</email>
</author>
<published>2013-08-28T01:45:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=229236a87b7b65e41cc2c1acc36e5bc610dd8c23'/>
<id>229236a87b7b65e41cc2c1acc36e5bc610dd8c23</id>
<content type='text'>
commit 4355b70cf48363c50a9de450b01178c83aba8f6a upstream.

Some bright specification writers decided to write this in the ONFI spec
(from ONFI 3.0, Section 3.1):

  "The number of blocks and number of pages per block is not required to
  be a power of two. In the case where one of these values is not a
  power of two, the corresponding address shall be rounded to an
  integral number of bits such that it addresses a range up to the
  subsequent power of two value. The host shall not access upper
  addresses in a range that is shown as not supported."

This breaks every assumption MTD makes about NAND block/chip-size
dimensions -- they *must* be a power of two!

And of course, an enterprising manufacturer has made use of this lovely
freedom. Exhibit A: Micron MT29F32G08CBADAWP

  "- Plane size: 2 planes x 1064 blocks per plane
   - Device size: 32Gb: 2128 blockss [sic]"

This quickly hits a BUG() in nand_base.c, since the extra dimensions
overflow so we think it's a second chip (on my single-chip setup):

    ONFI param page 0 valid
    ONFI flash detected
    NAND device: Manufacturer ID: 0x2c, Chip ID: 0x44 (Micron MT29F32G08CBADAWP), 4256MiB, page size: 8192, OOB size: 744
    ------------[ cut here ]------------
    kernel BUG at drivers/mtd/nand/nand_base.c:203!
    Internal error: Oops - BUG: 0 [#1] SMP ARM
    [... trim ...]
    [&lt;c02cf3e4&gt;] (nand_select_chip+0x18/0x2c) from [&lt;c02d25c0&gt;] (nand_do_read_ops+0x90/0x424)
    [&lt;c02d25c0&gt;] (nand_do_read_ops+0x90/0x424) from [&lt;c02d2dd8&gt;] (nand_read+0x54/0x78)
    [&lt;c02d2dd8&gt;] (nand_read+0x54/0x78) from [&lt;c02ad2c8&gt;] (mtd_read+0x84/0xbc)
    [&lt;c02ad2c8&gt;] (mtd_read+0x84/0xbc) from [&lt;c02d4b28&gt;] (scan_read.clone.4+0x4c/0x64)
    [&lt;c02d4b28&gt;] (scan_read.clone.4+0x4c/0x64) from [&lt;c02d4c88&gt;] (search_bbt+0x148/0x290)
    [&lt;c02d4c88&gt;] (search_bbt+0x148/0x290) from [&lt;c02d4ea4&gt;] (nand_scan_bbt+0xd4/0x5c0)
    [... trim ...]
    ---[ end trace 0c9363860d865ff2 ]---

So to fix this, just truncate these dimensions down to the greatest
power-of-2 dimension that is less than or equal to the specified
dimension.

Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
[bwh: Backported to 3.2:
 - Adjust context
 - p-&gt;lun_count is not used]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4355b70cf48363c50a9de450b01178c83aba8f6a upstream.

Some bright specification writers decided to write this in the ONFI spec
(from ONFI 3.0, Section 3.1):

  "The number of blocks and number of pages per block is not required to
  be a power of two. In the case where one of these values is not a
  power of two, the corresponding address shall be rounded to an
  integral number of bits such that it addresses a range up to the
  subsequent power of two value. The host shall not access upper
  addresses in a range that is shown as not supported."

This breaks every assumption MTD makes about NAND block/chip-size
dimensions -- they *must* be a power of two!

And of course, an enterprising manufacturer has made use of this lovely
freedom. Exhibit A: Micron MT29F32G08CBADAWP

  "- Plane size: 2 planes x 1064 blocks per plane
   - Device size: 32Gb: 2128 blockss [sic]"

This quickly hits a BUG() in nand_base.c, since the extra dimensions
overflow so we think it's a second chip (on my single-chip setup):

    ONFI param page 0 valid
    ONFI flash detected
    NAND device: Manufacturer ID: 0x2c, Chip ID: 0x44 (Micron MT29F32G08CBADAWP), 4256MiB, page size: 8192, OOB size: 744
    ------------[ cut here ]------------
    kernel BUG at drivers/mtd/nand/nand_base.c:203!
    Internal error: Oops - BUG: 0 [#1] SMP ARM
    [... trim ...]
    [&lt;c02cf3e4&gt;] (nand_select_chip+0x18/0x2c) from [&lt;c02d25c0&gt;] (nand_do_read_ops+0x90/0x424)
    [&lt;c02d25c0&gt;] (nand_do_read_ops+0x90/0x424) from [&lt;c02d2dd8&gt;] (nand_read+0x54/0x78)
    [&lt;c02d2dd8&gt;] (nand_read+0x54/0x78) from [&lt;c02ad2c8&gt;] (mtd_read+0x84/0xbc)
    [&lt;c02ad2c8&gt;] (mtd_read+0x84/0xbc) from [&lt;c02d4b28&gt;] (scan_read.clone.4+0x4c/0x64)
    [&lt;c02d4b28&gt;] (scan_read.clone.4+0x4c/0x64) from [&lt;c02d4c88&gt;] (search_bbt+0x148/0x290)
    [&lt;c02d4c88&gt;] (search_bbt+0x148/0x290) from [&lt;c02d4ea4&gt;] (nand_scan_bbt+0xd4/0x5c0)
    [... trim ...]
    ---[ end trace 0c9363860d865ff2 ]---

So to fix this, just truncate these dimensions down to the greatest
power-of-2 dimension that is less than or equal to the specified
dimension.

Signed-off-by: Brian Norris &lt;computersforpeace@gmail.com&gt;
[bwh: Backported to 3.2:
 - Adjust context
 - p-&gt;lun_count is not used]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: Disable mtdchar mmap on MMU systems</title>
<updated>2013-04-25T19:25:48+00:00</updated>
<author>
<name>David Woodhouse</name>
<email>David.Woodhouse@intel.com</email>
</author>
<published>2012-10-09T14:08:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=095a3cac24ab4bc77ca12efd6198ca237282801e'/>
<id>095a3cac24ab4bc77ca12efd6198ca237282801e</id>
<content type='text'>
commit f5cf8f07423b2677cebebcebc863af77223a4972 upstream.

This code was broken because it assumed that all MTD devices were map-based.
Disable it for now, until it can be fixed properly for the next merge window.

Signed-off-by: David Woodhouse &lt;David.Woodhouse@intel.com&gt;
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f5cf8f07423b2677cebebcebc863af77223a4972 upstream.

This code was broken because it assumed that all MTD devices were map-based.
Disable it for now, until it can be fixed properly for the next merge window.

Signed-off-by: David Woodhouse &lt;David.Woodhouse@intel.com&gt;
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: nand: gpmi: reset BCH earlier, too, to avoid NAND startup problems</title>
<updated>2013-01-03T03:33:39+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>w.sang@pengutronix.de</email>
</author>
<published>2012-12-05T20:46:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=86d5031c943445a561eae9c827d610e58a3325fd'/>
<id>86d5031c943445a561eae9c827d610e58a3325fd</id>
<content type='text'>
commit 6f2a6a52560ad8d85710aabd92b7a3239b3a6b07 upstream.

It could happen (1 out of 100 times) that NAND did not start up
correctly after warm rebooting, so the kernel could not find the UBI or
DMA timed out due to a stalled BCH. When resetting BCH together with
GPMI, the issue could not be observed anymore (after 10000+ reboots). We
probably need the consistent state already before sending any command to
NAND, even when no ECC is needed. I chose to keep the extra reset for
BCH when changing the flash layout to be on the safe side.

Signed-off-by: Wolfram Sang &lt;w.sang@pengutronix.de&gt;
Acked-by: Huang Shijie &lt;b32955@freescale.com&gt;
Signed-off-by: Artem Bityutskiy &lt;artem.bityutskiy@linux.intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6f2a6a52560ad8d85710aabd92b7a3239b3a6b07 upstream.

It could happen (1 out of 100 times) that NAND did not start up
correctly after warm rebooting, so the kernel could not find the UBI or
DMA timed out due to a stalled BCH. When resetting BCH together with
GPMI, the issue could not be observed anymore (after 10000+ reboots). We
probably need the consistent state already before sending any command to
NAND, even when no ECC is needed. I chose to keep the extra reset for
BCH when changing the flash layout to be on the safe side.

Signed-off-by: Wolfram Sang &lt;w.sang@pengutronix.de&gt;
Acked-by: Huang Shijie &lt;b32955@freescale.com&gt;
Signed-off-by: Artem Bityutskiy &lt;artem.bityutskiy@linux.intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: slram: invalid checking of absolute end address</title>
<updated>2012-12-06T11:20:22+00:00</updated>
<author>
<name>Jiri Engelthaler</name>
<email>engycz@gmail.com</email>
</author>
<published>2012-09-20T14:49:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c714d5ebaa83ad49965b17b5aa8c8e732b27b60d'/>
<id>c714d5ebaa83ad49965b17b5aa8c8e732b27b60d</id>
<content type='text'>
commit c36a7ff4578ab6294885aef5ef241aeec4cdb1f0 upstream.

Fixed parsing end absolute address.

Signed-off-by: Jiri Engelthaler &lt;engycz@gmail.com&gt;
Signed-off-by: Artem Bityutskiy &lt;artem.bityutskiy@linux.intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c36a7ff4578ab6294885aef5ef241aeec4cdb1f0 upstream.

Fixed parsing end absolute address.

Signed-off-by: Jiri Engelthaler &lt;engycz@gmail.com&gt;
Signed-off-by: Artem Bityutskiy &lt;artem.bityutskiy@linux.intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mtd: ofpart: Fix incorrect NULL check in parse_ofoldpart_partitions()</title>
<updated>2012-12-06T11:20:21+00:00</updated>
<author>
<name>Sachin Kamat</name>
<email>sachin.kamat@linaro.org</email>
</author>
<published>2012-09-25T09:57:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=016ede1a94fbd90c2a24a82599859f9e46e3c298'/>
<id>016ede1a94fbd90c2a24a82599859f9e46e3c298</id>
<content type='text'>
commit 5a6ea4af0907f995dc06df21a9c9ef764c7cd3bc upstream.

The pointer returned by kzalloc should be tested for NULL
to avoid potential NULL pointer dereference later. Incorrect
pointer was being tested for NULL. Bug introduced by commit fbcf62a3
(mtd: physmap_of: move parse_obsolete_partitions to become separate
parser).
This patch fixes this bug.

Cc: Dmitry Eremin-Solenikov &lt;dbaryshkov@gmail.com&gt;
Cc: Artem Bityutskiy &lt;artem.bityutskiy@intel.com&gt;
Signed-off-by: Sachin Kamat &lt;sachin.kamat@linaro.org&gt;
Signed-off-by: David Woodhouse &lt;David.Woodhouse@intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5a6ea4af0907f995dc06df21a9c9ef764c7cd3bc upstream.

The pointer returned by kzalloc should be tested for NULL
to avoid potential NULL pointer dereference later. Incorrect
pointer was being tested for NULL. Bug introduced by commit fbcf62a3
(mtd: physmap_of: move parse_obsolete_partitions to become separate
parser).
This patch fixes this bug.

Cc: Dmitry Eremin-Solenikov &lt;dbaryshkov@gmail.com&gt;
Cc: Artem Bityutskiy &lt;artem.bityutskiy@intel.com&gt;
Signed-off-by: Sachin Kamat &lt;sachin.kamat@linaro.org&gt;
Signed-off-by: David Woodhouse &lt;David.Woodhouse@intel.com&gt;
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
</pre>
</div>
</content>
</entry>
</feed>
