<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/include, branch v3.4.108</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>PCI: Convert pcibios_resource_to_bus() to take a pci_bus, not a pci_dev</title>
<updated>2015-06-19T03:40:34+00:00</updated>
<author>
<name>Yinghai Lu</name>
<email>yinghai@kernel.org</email>
</author>
<published>2013-12-10T06:54:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bded67cc51db4e29af84f9ec1d671a86b0b6763b'/>
<id>bded67cc51db4e29af84f9ec1d671a86b0b6763b</id>
<content type='text'>
commit fc2798502f860b18f3c7121e4dc659d3d9d28d74 upstream.

These interfaces:

  pcibios_resource_to_bus(struct pci_dev *dev, *bus_region, *resource)
  pcibios_bus_to_resource(struct pci_dev *dev, *resource, *bus_region)

took a pci_dev, but they really depend only on the pci_bus.  And we want to
use them in resource allocation paths where we have the bus but not a
device, so this patch converts them to take the pci_bus instead of the
pci_dev:

  pcibios_resource_to_bus(struct pci_bus *bus, *bus_region, *resource)
  pcibios_bus_to_resource(struct pci_bus *bus, *resource, *bus_region)

In fact, with standard PCI-PCI bridges, they only depend on the host
bridge, because that's the only place address translation occurs, but
we aren't going that far yet.

[bhelgaas: changelog]
Signed-off-by: Yinghai Lu &lt;yinghai@kernel.org&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: Dirk Behme &lt;dirk.behme@gmail.com&gt;
[lizf: Backported to 3.4:
 - make changes to pci_host_bridge() instead of find_pci_root_bus()
 - adjust context]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit fc2798502f860b18f3c7121e4dc659d3d9d28d74 upstream.

These interfaces:

  pcibios_resource_to_bus(struct pci_dev *dev, *bus_region, *resource)
  pcibios_bus_to_resource(struct pci_dev *dev, *resource, *bus_region)

took a pci_dev, but they really depend only on the pci_bus.  And we want to
use them in resource allocation paths where we have the bus but not a
device, so this patch converts them to take the pci_bus instead of the
pci_dev:

  pcibios_resource_to_bus(struct pci_bus *bus, *bus_region, *resource)
  pcibios_bus_to_resource(struct pci_bus *bus, *resource, *bus_region)

In fact, with standard PCI-PCI bridges, they only depend on the host
bridge, because that's the only place address translation occurs, but
we aren't going that far yet.

[bhelgaas: changelog]
Signed-off-by: Yinghai Lu &lt;yinghai@kernel.org&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Cc: Dirk Behme &lt;dirk.behme@gmail.com&gt;
[lizf: Backported to 3.4:
 - make changes to pci_host_bridge() instead of find_pci_root_bus()
 - adjust context]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Defer processing of REQ_PREEMPT requests for blocked devices</title>
<updated>2015-06-19T03:40:31+00:00</updated>
<author>
<name>Bart Van Assche</name>
<email>bart.vanassche@sandisk.com</email>
</author>
<published>2015-03-04T09:31:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=419d4c989459c5fa2d3fa42c061c097e53dcaf19'/>
<id>419d4c989459c5fa2d3fa42c061c097e53dcaf19</id>
<content type='text'>
commit bba0bdd7ad4713d82338bcd9b72d57e9335a664b upstream.

SCSI transport drivers and SCSI LLDs block a SCSI device if the
transport layer is not operational. This means that in this state
no requests should be processed, even if the REQ_PREEMPT flag has
been set. This patch avoids that a rescan shortly after a cable
pull sporadically triggers the following kernel oops:

BUG: unable to handle kernel paging request at ffffc9001a6bc084
IP: [&lt;ffffffffa04e08f2&gt;] mlx4_ib_post_send+0xd2/0xb30 [mlx4_ib]
Process rescan-scsi-bus (pid: 9241, threadinfo ffff88053484a000, task ffff880534aae100)
Call Trace:
 [&lt;ffffffffa0718135&gt;] srp_post_send+0x65/0x70 [ib_srp]
 [&lt;ffffffffa071b9df&gt;] srp_queuecommand+0x1cf/0x3e0 [ib_srp]
 [&lt;ffffffffa0001ff1&gt;] scsi_dispatch_cmd+0x101/0x280 [scsi_mod]
 [&lt;ffffffffa0009ad1&gt;] scsi_request_fn+0x411/0x4d0 [scsi_mod]
 [&lt;ffffffff81223b37&gt;] __blk_run_queue+0x27/0x30
 [&lt;ffffffff8122a8d2&gt;] blk_execute_rq_nowait+0x82/0x110
 [&lt;ffffffff8122a9c2&gt;] blk_execute_rq+0x62/0xf0
 [&lt;ffffffffa000b0e8&gt;] scsi_execute+0xe8/0x190 [scsi_mod]
 [&lt;ffffffffa000b2f3&gt;] scsi_execute_req+0xa3/0x130 [scsi_mod]
 [&lt;ffffffffa000c1aa&gt;] scsi_probe_lun+0x17a/0x450 [scsi_mod]
 [&lt;ffffffffa000ce86&gt;] scsi_probe_and_add_lun+0x156/0x480 [scsi_mod]
 [&lt;ffffffffa000dc2f&gt;] __scsi_scan_target+0xdf/0x1f0 [scsi_mod]
 [&lt;ffffffffa000dfa3&gt;] scsi_scan_host_selected+0x183/0x1c0 [scsi_mod]
 [&lt;ffffffffa000edfb&gt;] scsi_scan+0xdb/0xe0 [scsi_mod]
 [&lt;ffffffffa000ee13&gt;] store_scan+0x13/0x20 [scsi_mod]
 [&lt;ffffffff811c8d9b&gt;] sysfs_write_file+0xcb/0x160
 [&lt;ffffffff811589de&gt;] vfs_write+0xce/0x140
 [&lt;ffffffff81158b53&gt;] sys_write+0x53/0xa0
 [&lt;ffffffff81464592&gt;] system_call_fastpath+0x16/0x1b
 [&lt;00007f611c9d9300&gt;] 0x7f611c9d92ff

Reported-by: Max Gurtuvoy &lt;maxg@mellanox.com&gt;
Signed-off-by: Bart Van Assche &lt;bart.vanassche@sandisk.com&gt;
Reviewed-by: Mike Christie &lt;michaelc@cs.wisc.edu&gt;
Signed-off-by: James Bottomley &lt;JBottomley@Odin.com&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit bba0bdd7ad4713d82338bcd9b72d57e9335a664b upstream.

SCSI transport drivers and SCSI LLDs block a SCSI device if the
transport layer is not operational. This means that in this state
no requests should be processed, even if the REQ_PREEMPT flag has
been set. This patch avoids that a rescan shortly after a cable
pull sporadically triggers the following kernel oops:

BUG: unable to handle kernel paging request at ffffc9001a6bc084
IP: [&lt;ffffffffa04e08f2&gt;] mlx4_ib_post_send+0xd2/0xb30 [mlx4_ib]
Process rescan-scsi-bus (pid: 9241, threadinfo ffff88053484a000, task ffff880534aae100)
Call Trace:
 [&lt;ffffffffa0718135&gt;] srp_post_send+0x65/0x70 [ib_srp]
 [&lt;ffffffffa071b9df&gt;] srp_queuecommand+0x1cf/0x3e0 [ib_srp]
 [&lt;ffffffffa0001ff1&gt;] scsi_dispatch_cmd+0x101/0x280 [scsi_mod]
 [&lt;ffffffffa0009ad1&gt;] scsi_request_fn+0x411/0x4d0 [scsi_mod]
 [&lt;ffffffff81223b37&gt;] __blk_run_queue+0x27/0x30
 [&lt;ffffffff8122a8d2&gt;] blk_execute_rq_nowait+0x82/0x110
 [&lt;ffffffff8122a9c2&gt;] blk_execute_rq+0x62/0xf0
 [&lt;ffffffffa000b0e8&gt;] scsi_execute+0xe8/0x190 [scsi_mod]
 [&lt;ffffffffa000b2f3&gt;] scsi_execute_req+0xa3/0x130 [scsi_mod]
 [&lt;ffffffffa000c1aa&gt;] scsi_probe_lun+0x17a/0x450 [scsi_mod]
 [&lt;ffffffffa000ce86&gt;] scsi_probe_and_add_lun+0x156/0x480 [scsi_mod]
 [&lt;ffffffffa000dc2f&gt;] __scsi_scan_target+0xdf/0x1f0 [scsi_mod]
 [&lt;ffffffffa000dfa3&gt;] scsi_scan_host_selected+0x183/0x1c0 [scsi_mod]
 [&lt;ffffffffa000edfb&gt;] scsi_scan+0xdb/0xe0 [scsi_mod]
 [&lt;ffffffffa000ee13&gt;] store_scan+0x13/0x20 [scsi_mod]
 [&lt;ffffffff811c8d9b&gt;] sysfs_write_file+0xcb/0x160
 [&lt;ffffffff811589de&gt;] vfs_write+0xce/0x140
 [&lt;ffffffff81158b53&gt;] sys_write+0x53/0xa0
 [&lt;ffffffff81464592&gt;] system_call_fastpath+0x16/0x1b
 [&lt;00007f611c9d9300&gt;] 0x7f611c9d92ff

Reported-by: Max Gurtuvoy &lt;maxg@mellanox.com&gt;
Signed-off-by: Bart Van Assche &lt;bart.vanassche@sandisk.com&gt;
Reviewed-by: Mike Christie &lt;michaelc@cs.wisc.edu&gt;
Signed-off-by: James Bottomley &lt;JBottomley@Odin.com&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fsnotify: fix handling of renames in audit</title>
<updated>2015-06-19T03:40:14+00:00</updated>
<author>
<name>Jan Kara</name>
<email>jack@suse.cz</email>
</author>
<published>2015-02-10T22:08:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c93fc8932e95ace45c35fe7a7220acd866bc5ae0'/>
<id>c93fc8932e95ace45c35fe7a7220acd866bc5ae0</id>
<content type='text'>
commit 6ee8e25fc3e916193bce4ebb43d5439e1e2144ab upstream.

Commit e9fd702a58c4 ("audit: convert audit watches to use fsnotify
instead of inotify") broke handling of renames in audit.  Audit code
wants to update inode number of an inode corresponding to watched name
in a directory.  When something gets renamed into a directory to a
watched name, inotify previously passed moved inode to audit code
however new fsnotify code passes directory inode where the change
happened.  That confuses audit and it starts watching parent directory
instead of a file in a directory.

This can be observed for example by doing:

  cd /tmp
  touch foo bar
  auditctl -w /tmp/foo
  touch foo
  mv bar foo
  touch foo

In audit log we see events like:

  type=CONFIG_CHANGE msg=audit(1423563584.155:90): auid=1000 ses=2 op="updated rules" path="/tmp/foo" key=(null) list=4 res=1
  ...
  type=PATH msg=audit(1423563584.155:91): item=2 name="bar" inode=1046884 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=DELETE
  type=PATH msg=audit(1423563584.155:91): item=3 name="foo" inode=1046842 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=DELETE
  type=PATH msg=audit(1423563584.155:91): item=4 name="foo" inode=1046884 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=CREATE
  ...

and that's it - we see event for the first touch after creating the
audit rule, we see events for rename but we don't see any event for the
last touch.  However we start seeing events for unrelated stuff
happening in /tmp.

Fix the problem by passing moved inode as data in the FS_MOVED_FROM and
FS_MOVED_TO events instead of the directory where the change happens.
This doesn't introduce any new problems because noone besides
audit_watch.c cares about the passed value:

  fs/notify/fanotify/fanotify.c cares only about FSNOTIFY_EVENT_PATH events.
  fs/notify/dnotify/dnotify.c doesn't care about passed 'data' value at all.
  fs/notify/inotify/inotify_fsnotify.c uses 'data' only for FSNOTIFY_EVENT_PATH.
  kernel/audit_tree.c doesn't care about passed 'data' at all.
  kernel/audit_watch.c expects moved inode as 'data'.

Fixes: e9fd702a58c49db ("audit: convert audit watches to use fsnotify instead of inotify")
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
Cc: Paul Moore &lt;paul@paul-moore.com&gt;
Cc: Eric Paris &lt;eparis@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6ee8e25fc3e916193bce4ebb43d5439e1e2144ab upstream.

Commit e9fd702a58c4 ("audit: convert audit watches to use fsnotify
instead of inotify") broke handling of renames in audit.  Audit code
wants to update inode number of an inode corresponding to watched name
in a directory.  When something gets renamed into a directory to a
watched name, inotify previously passed moved inode to audit code
however new fsnotify code passes directory inode where the change
happened.  That confuses audit and it starts watching parent directory
instead of a file in a directory.

This can be observed for example by doing:

  cd /tmp
  touch foo bar
  auditctl -w /tmp/foo
  touch foo
  mv bar foo
  touch foo

In audit log we see events like:

  type=CONFIG_CHANGE msg=audit(1423563584.155:90): auid=1000 ses=2 op="updated rules" path="/tmp/foo" key=(null) list=4 res=1
  ...
  type=PATH msg=audit(1423563584.155:91): item=2 name="bar" inode=1046884 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=DELETE
  type=PATH msg=audit(1423563584.155:91): item=3 name="foo" inode=1046842 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=DELETE
  type=PATH msg=audit(1423563584.155:91): item=4 name="foo" inode=1046884 dev=08:0 2 mode=0100644 ouid=0 ogid=0 rdev=00:00 nametype=CREATE
  ...

and that's it - we see event for the first touch after creating the
audit rule, we see events for rename but we don't see any event for the
last touch.  However we start seeing events for unrelated stuff
happening in /tmp.

Fix the problem by passing moved inode as data in the FS_MOVED_FROM and
FS_MOVED_TO events instead of the directory where the change happens.
This doesn't introduce any new problems because noone besides
audit_watch.c cares about the passed value:

  fs/notify/fanotify/fanotify.c cares only about FSNOTIFY_EVENT_PATH events.
  fs/notify/dnotify/dnotify.c doesn't care about passed 'data' value at all.
  fs/notify/inotify/inotify_fsnotify.c uses 'data' only for FSNOTIFY_EVENT_PATH.
  kernel/audit_tree.c doesn't care about passed 'data' at all.
  kernel/audit_watch.c expects moved inode as 'data'.

Fixes: e9fd702a58c49db ("audit: convert audit watches to use fsnotify instead of inotify")
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
Cc: Paul Moore &lt;paul@paul-moore.com&gt;
Cc: Eric Paris &lt;eparis@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: add flag for HCDs that can't receive wakeup requests (isp1760-hcd)</title>
<updated>2015-06-19T03:40:13+00:00</updated>
<author>
<name>Alan Stern</name>
<email>stern@rowland.harvard.edu</email>
</author>
<published>2015-01-29T20:05:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=019b694fbccafebc550a7b1fcb3bb13e9b32ae03'/>
<id>019b694fbccafebc550a7b1fcb3bb13e9b32ae03</id>
<content type='text'>
commit 074f9dd55f9cab1b82690ed7e44bcf38b9616ce0 upstream.

Currently the USB stack assumes that all host controller drivers are
capable of receiving wakeup requests from downstream devices.
However, this isn't true for the isp1760-hcd driver, which means that
it isn't safe to do a runtime suspend of any device attached to a
root-hub port if the device requires wakeup.

This patch adds a "cant_recv_wakeups" flag to the usb_hcd structure
and sets the flag in isp1760-hcd.  The core is modified to prevent a
direct child of the root hub from being put into runtime suspend with
wakeup enabled if the flag is set.

Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Tested-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;greg@kroah.com&gt;
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 074f9dd55f9cab1b82690ed7e44bcf38b9616ce0 upstream.

Currently the USB stack assumes that all host controller drivers are
capable of receiving wakeup requests from downstream devices.
However, this isn't true for the isp1760-hcd driver, which means that
it isn't safe to do a runtime suspend of any device attached to a
root-hub port if the device requires wakeup.

This patch adds a "cant_recv_wakeups" flag to the usb_hcd structure
and sets the flag in isp1760-hcd.  The core is modified to prevent a
direct child of the root hub from being put into runtime suspend with
wakeup enabled if the flag is set.

Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Tested-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;greg@kroah.com&gt;
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: core: buffer: smallest buffer should start at ARCH_DMA_MINALIGN</title>
<updated>2015-06-19T03:40:11+00:00</updated>
<author>
<name>Sebastian Andrzej Siewior</name>
<email>bigeasy@linutronix.de</email>
</author>
<published>2014-12-05T14:13:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=aef29c3576fb89843193a2a026719a0fdb4145ab'/>
<id>aef29c3576fb89843193a2a026719a0fdb4145ab</id>
<content type='text'>
commit 5efd2ea8c9f4f12916ffc8ba636792ce052f6911 upstream.

the following error pops up during "testusb -a -t 10"
| musb-hdrc musb-hdrc.1.auto: dma_pool_free buffer-128,	f134e000/be842000 (bad dma)
hcd_buffer_create() creates a few buffers, the smallest has 32 bytes of
size. ARCH_KMALLOC_MINALIGN is set to 64 bytes. This combo results in
hcd_buffer_alloc() returning memory which is 32 bytes aligned and it
might by identified by buffer_offset() as another buffer. This means the
buffer which is on a 32 byte boundary will not get freed, instead it
tries to free another buffer with the error message.

This patch fixes the issue by creating the smallest DMA buffer with the
size of ARCH_KMALLOC_MINALIGN (or 32 in case ARCH_KMALLOC_MINALIGN is
smaller). This might be 32, 64 or even 128 bytes. The next three pools
will have the size 128, 512 and 2048.
In case the smallest pool is 128 bytes then we have only three pools
instead of four (and zero the first entry in the array).
The last pool size is always 2048 bytes which is the assumed PAGE_SIZE /
2 of 4096. I doubt it makes sense to continue using PAGE_SIZE / 2 where
we would end up with 8KiB buffer in case we have 16KiB pages.
Instead I think it makes sense to have a common size(s) and extend them
if there is need to.
There is a BUILD_BUG_ON() now in case someone has a minalign of more than
128 bytes.

Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5efd2ea8c9f4f12916ffc8ba636792ce052f6911 upstream.

the following error pops up during "testusb -a -t 10"
| musb-hdrc musb-hdrc.1.auto: dma_pool_free buffer-128,	f134e000/be842000 (bad dma)
hcd_buffer_create() creates a few buffers, the smallest has 32 bytes of
size. ARCH_KMALLOC_MINALIGN is set to 64 bytes. This combo results in
hcd_buffer_alloc() returning memory which is 32 bytes aligned and it
might by identified by buffer_offset() as another buffer. This means the
buffer which is on a 32 byte boundary will not get freed, instead it
tries to free another buffer with the error message.

This patch fixes the issue by creating the smallest DMA buffer with the
size of ARCH_KMALLOC_MINALIGN (or 32 in case ARCH_KMALLOC_MINALIGN is
smaller). This might be 32, 64 or even 128 bytes. The next three pools
will have the size 128, 512 and 2048.
In case the smallest pool is 128 bytes then we have only three pools
instead of four (and zero the first entry in the array).
The last pool size is always 2048 bytes which is the assumed PAGE_SIZE /
2 of 4096. I doubt it makes sense to continue using PAGE_SIZE / 2 where
we would end up with 8KiB buffer in case we have 16KiB pages.
Instead I think it makes sense to have a common size(s) and extend them
if there is need to.
There is a BUILD_BUG_ON() now in case someone has a minalign of more than
128 bytes.

Signed-off-by: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ALSA: ak411x: Fix stall in work callback</title>
<updated>2015-04-14T09:33:59+00:00</updated>
<author>
<name>Takashi Iwai</name>
<email>tiwai@suse.de</email>
</author>
<published>2015-01-13T09:53:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=574b59db6504ed3867c2f566f167f764e97ee402'/>
<id>574b59db6504ed3867c2f566f167f764e97ee402</id>
<content type='text'>
commit 4161b4505f1690358ac0a9ee59845a7887336b21 upstream.

When ak4114 work calls its callback and the callback invokes
ak4114_reinit(), it stalls due to flush_delayed_work().  For avoiding
this, control the reentrance by introducing a refcount.  Also
flush_delayed_work() is replaced with cancel_delayed_work_sync().

The exactly same bug is present in ak4113.c and fixed as well.

Reported-by: Pavel Hofman &lt;pavel.hofman@ivitera.com&gt;
Acked-by: Jaroslav Kysela &lt;perex@perex.cz&gt;
Tested-by: Pavel Hofman &lt;pavel.hofman@ivitera.com&gt;
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
[lizf: Backported to 3.4: snd_ak4113_reinit() and snd_ak4114_reinit()
used flush_delayed_work_sync() instead of flush_delayed_work()]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 4161b4505f1690358ac0a9ee59845a7887336b21 upstream.

When ak4114 work calls its callback and the callback invokes
ak4114_reinit(), it stalls due to flush_delayed_work().  For avoiding
this, control the reentrance by introducing a refcount.  Also
flush_delayed_work() is replaced with cancel_delayed_work_sync().

The exactly same bug is present in ak4113.c and fixed as well.

Reported-by: Pavel Hofman &lt;pavel.hofman@ivitera.com&gt;
Acked-by: Jaroslav Kysela &lt;perex@perex.cz&gt;
Tested-by: Pavel Hofman &lt;pavel.hofman@ivitera.com&gt;
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
[lizf: Backported to 3.4: snd_ak4113_reinit() and snd_ak4114_reinit()
used flush_delayed_work_sync() instead of flush_delayed_work()]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>move d_rcu from overlapping d_child to overlapping d_alias</title>
<updated>2015-04-14T09:33:58+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2014-10-26T23:19:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6fd17def6d964c81205230e02b4208c653106d51'/>
<id>6fd17def6d964c81205230e02b4208c653106d51</id>
<content type='text'>
commit 946e51f2bf37f1656916eb75bd0742ba33983c28 upstream.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
[bwh: Backported to 3.2:
 - Apply name changes in all the different places we use d_alias and d_child
 - Move the WARN_ON() in __d_free() to d_free() as we don't have dentry_free()]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
[lizf: Backported to 3.4:
 - adjust context
 - need one more name change in debugfs]
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 946e51f2bf37f1656916eb75bd0742ba33983c28 upstream.

Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
[bwh: Backported to 3.2:
 - Apply name changes in all the different places we use d_alias and d_child
 - Move the WARN_ON() in __d_free() to d_free() as we don't have dentry_free()]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
[lizf: Backported to 3.4:
 - adjust context
 - need one more name change in debugfs]
</pre>
</div>
</content>
</entry>
<entry>
<title>net: sctp: fix skb_over_panic when receiving malformed ASCONF chunks</title>
<updated>2015-04-14T09:33:57+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>dborkman@redhat.com</email>
</author>
<published>2014-10-09T20:55:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b0f741c5d11b1b2bafd8392f0cb4d8ac25be9164'/>
<id>b0f741c5d11b1b2bafd8392f0cb4d8ac25be9164</id>
<content type='text'>
commit 9de7922bc709eee2f609cd01d98aaedc4cf5ea74 upstream.

Commit 6f4c618ddb0 ("SCTP : Add paramters validity check for
ASCONF chunk") added basic verification of ASCONF chunks, however,
it is still possible to remotely crash a server by sending a
special crafted ASCONF chunk, even up to pre 2.6.12 kernels:

skb_over_panic: text:ffffffffa01ea1c3 len:31056 put:30768
 head:ffff88011bd81800 data:ffff88011bd81800 tail:0x7950
 end:0x440 dev:&lt;NULL&gt;
 ------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:129!
[...]
Call Trace:
 &lt;IRQ&gt;
 [&lt;ffffffff8144fb1c&gt;] skb_put+0x5c/0x70
 [&lt;ffffffffa01ea1c3&gt;] sctp_addto_chunk+0x63/0xd0 [sctp]
 [&lt;ffffffffa01eadaf&gt;] sctp_process_asconf+0x1af/0x540 [sctp]
 [&lt;ffffffff8152d025&gt;] ? _read_unlock_bh+0x15/0x20
 [&lt;ffffffffa01e0038&gt;] sctp_sf_do_asconf+0x168/0x240 [sctp]
 [&lt;ffffffffa01e3751&gt;] sctp_do_sm+0x71/0x1210 [sctp]
 [&lt;ffffffff8147645d&gt;] ? fib_rules_lookup+0xad/0xf0
 [&lt;ffffffffa01e6b22&gt;] ? sctp_cmp_addr_exact+0x32/0x40 [sctp]
 [&lt;ffffffffa01e8393&gt;] sctp_assoc_bh_rcv+0xd3/0x180 [sctp]
 [&lt;ffffffffa01ee986&gt;] sctp_inq_push+0x56/0x80 [sctp]
 [&lt;ffffffffa01fcc42&gt;] sctp_rcv+0x982/0xa10 [sctp]
 [&lt;ffffffffa01d5123&gt;] ? ipt_local_in_hook+0x23/0x28 [iptable_filter]
 [&lt;ffffffff8148bdc9&gt;] ? nf_iterate+0x69/0xb0
 [&lt;ffffffff81496d10&gt;] ? ip_local_deliver_finish+0x0/0x2d0
 [&lt;ffffffff8148bf86&gt;] ? nf_hook_slow+0x76/0x120
 [&lt;ffffffff81496d10&gt;] ? ip_local_deliver_finish+0x0/0x2d0
 [&lt;ffffffff81496ded&gt;] ip_local_deliver_finish+0xdd/0x2d0
 [&lt;ffffffff81497078&gt;] ip_local_deliver+0x98/0xa0
 [&lt;ffffffff8149653d&gt;] ip_rcv_finish+0x12d/0x440
 [&lt;ffffffff81496ac5&gt;] ip_rcv+0x275/0x350
 [&lt;ffffffff8145c88b&gt;] __netif_receive_skb+0x4ab/0x750
 [&lt;ffffffff81460588&gt;] netif_receive_skb+0x58/0x60

This can be triggered e.g., through a simple scripted nmap
connection scan injecting the chunk after the handshake, for
example, ...

  -------------- INIT[ASCONF; ASCONF_ACK] -------------&gt;
  &lt;----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------
  -------------------- COOKIE-ECHO --------------------&gt;
  &lt;-------------------- COOKIE-ACK ---------------------
  ------------------ ASCONF; UNKNOWN ------------------&gt;

... where ASCONF chunk of length 280 contains 2 parameters ...

  1) Add IP address parameter (param length: 16)
  2) Add/del IP address parameter (param length: 255)

... followed by an UNKNOWN chunk of e.g. 4 bytes. Here, the
Address Parameter in the ASCONF chunk is even missing, too.
This is just an example and similarly-crafted ASCONF chunks
could be used just as well.

The ASCONF chunk passes through sctp_verify_asconf() as all
parameters passed sanity checks, and after walking, we ended
up successfully at the chunk end boundary, and thus may invoke
sctp_process_asconf(). Parameter walking is done with
WORD_ROUND() to take padding into account.

In sctp_process_asconf()'s TLV processing, we may fail in
sctp_process_asconf_param() e.g., due to removal of the IP
address that is also the source address of the packet containing
the ASCONF chunk, and thus we need to add all TLVs after the
failure to our ASCONF response to remote via helper function
sctp_add_asconf_response(), which basically invokes a
sctp_addto_chunk() adding the error parameters to the given
skb.

When walking to the next parameter this time, we proceed
with ...

  length = ntohs(asconf_param-&gt;param_hdr.length);
  asconf_param = (void *)asconf_param + length;

... instead of the WORD_ROUND()'ed length, thus resulting here
in an off-by-one that leads to reading the follow-up garbage
parameter length of 12336, and thus throwing an skb_over_panic
for the reply when trying to sctp_addto_chunk() next time,
which implicitly calls the skb_put() with that length.

Fix it by using sctp_walk_params() [ which is also used in
INIT parameter processing ] macro in the verification *and*
in ASCONF processing: it will make sure we don't spill over,
that we walk parameters WORD_ROUND()'ed. Moreover, we're being
more defensive and guard against unknown parameter types and
missized addresses.

Joint work with Vlad Yasevich.

Fixes: b896b82be4ae ("[SCTP] ADDIP: Support for processing incoming ASCONF_ACK chunks.")
Signed-off-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Signed-off-by: Vlad Yasevich &lt;vyasevich@gmail.com&gt;
Acked-by: Neil Horman &lt;nhorman@tuxdriver.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9de7922bc709eee2f609cd01d98aaedc4cf5ea74 upstream.

Commit 6f4c618ddb0 ("SCTP : Add paramters validity check for
ASCONF chunk") added basic verification of ASCONF chunks, however,
it is still possible to remotely crash a server by sending a
special crafted ASCONF chunk, even up to pre 2.6.12 kernels:

skb_over_panic: text:ffffffffa01ea1c3 len:31056 put:30768
 head:ffff88011bd81800 data:ffff88011bd81800 tail:0x7950
 end:0x440 dev:&lt;NULL&gt;
 ------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:129!
[...]
Call Trace:
 &lt;IRQ&gt;
 [&lt;ffffffff8144fb1c&gt;] skb_put+0x5c/0x70
 [&lt;ffffffffa01ea1c3&gt;] sctp_addto_chunk+0x63/0xd0 [sctp]
 [&lt;ffffffffa01eadaf&gt;] sctp_process_asconf+0x1af/0x540 [sctp]
 [&lt;ffffffff8152d025&gt;] ? _read_unlock_bh+0x15/0x20
 [&lt;ffffffffa01e0038&gt;] sctp_sf_do_asconf+0x168/0x240 [sctp]
 [&lt;ffffffffa01e3751&gt;] sctp_do_sm+0x71/0x1210 [sctp]
 [&lt;ffffffff8147645d&gt;] ? fib_rules_lookup+0xad/0xf0
 [&lt;ffffffffa01e6b22&gt;] ? sctp_cmp_addr_exact+0x32/0x40 [sctp]
 [&lt;ffffffffa01e8393&gt;] sctp_assoc_bh_rcv+0xd3/0x180 [sctp]
 [&lt;ffffffffa01ee986&gt;] sctp_inq_push+0x56/0x80 [sctp]
 [&lt;ffffffffa01fcc42&gt;] sctp_rcv+0x982/0xa10 [sctp]
 [&lt;ffffffffa01d5123&gt;] ? ipt_local_in_hook+0x23/0x28 [iptable_filter]
 [&lt;ffffffff8148bdc9&gt;] ? nf_iterate+0x69/0xb0
 [&lt;ffffffff81496d10&gt;] ? ip_local_deliver_finish+0x0/0x2d0
 [&lt;ffffffff8148bf86&gt;] ? nf_hook_slow+0x76/0x120
 [&lt;ffffffff81496d10&gt;] ? ip_local_deliver_finish+0x0/0x2d0
 [&lt;ffffffff81496ded&gt;] ip_local_deliver_finish+0xdd/0x2d0
 [&lt;ffffffff81497078&gt;] ip_local_deliver+0x98/0xa0
 [&lt;ffffffff8149653d&gt;] ip_rcv_finish+0x12d/0x440
 [&lt;ffffffff81496ac5&gt;] ip_rcv+0x275/0x350
 [&lt;ffffffff8145c88b&gt;] __netif_receive_skb+0x4ab/0x750
 [&lt;ffffffff81460588&gt;] netif_receive_skb+0x58/0x60

This can be triggered e.g., through a simple scripted nmap
connection scan injecting the chunk after the handshake, for
example, ...

  -------------- INIT[ASCONF; ASCONF_ACK] -------------&gt;
  &lt;----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------
  -------------------- COOKIE-ECHO --------------------&gt;
  &lt;-------------------- COOKIE-ACK ---------------------
  ------------------ ASCONF; UNKNOWN ------------------&gt;

... where ASCONF chunk of length 280 contains 2 parameters ...

  1) Add IP address parameter (param length: 16)
  2) Add/del IP address parameter (param length: 255)

... followed by an UNKNOWN chunk of e.g. 4 bytes. Here, the
Address Parameter in the ASCONF chunk is even missing, too.
This is just an example and similarly-crafted ASCONF chunks
could be used just as well.

The ASCONF chunk passes through sctp_verify_asconf() as all
parameters passed sanity checks, and after walking, we ended
up successfully at the chunk end boundary, and thus may invoke
sctp_process_asconf(). Parameter walking is done with
WORD_ROUND() to take padding into account.

In sctp_process_asconf()'s TLV processing, we may fail in
sctp_process_asconf_param() e.g., due to removal of the IP
address that is also the source address of the packet containing
the ASCONF chunk, and thus we need to add all TLVs after the
failure to our ASCONF response to remote via helper function
sctp_add_asconf_response(), which basically invokes a
sctp_addto_chunk() adding the error parameters to the given
skb.

When walking to the next parameter this time, we proceed
with ...

  length = ntohs(asconf_param-&gt;param_hdr.length);
  asconf_param = (void *)asconf_param + length;

... instead of the WORD_ROUND()'ed length, thus resulting here
in an off-by-one that leads to reading the follow-up garbage
parameter length of 12336, and thus throwing an skb_over_panic
for the reply when trying to sctp_addto_chunk() next time,
which implicitly calls the skb_put() with that length.

Fix it by using sctp_walk_params() [ which is also used in
INIT parameter processing ] macro in the verification *and*
in ASCONF processing: it will make sure we don't spill over,
that we walk parameters WORD_ROUND()'ed. Moreover, we're being
more defensive and guard against unknown parameter types and
missized addresses.

Joint work with Vlad Yasevich.

Fixes: b896b82be4ae ("[SCTP] ADDIP: Support for processing incoming ASCONF_ACK chunks.")
Signed-off-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Signed-off-by: Vlad Yasevich &lt;vyasevich@gmail.com&gt;
Acked-by: Neil Horman &lt;nhorman@tuxdriver.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: sctp: fix panic on duplicate ASCONF chunks</title>
<updated>2015-04-14T09:33:57+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>dborkman@redhat.com</email>
</author>
<published>2014-10-09T20:55:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d3fdf67442c2c1c97390176ce3451a6ae48450fe'/>
<id>d3fdf67442c2c1c97390176ce3451a6ae48450fe</id>
<content type='text'>
commit b69040d8e39f20d5215a03502a8e8b4c6ab78395 upstream.

When receiving a e.g. semi-good formed connection scan in the
form of ...

  -------------- INIT[ASCONF; ASCONF_ACK] -------------&gt;
  &lt;----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------
  -------------------- COOKIE-ECHO --------------------&gt;
  &lt;-------------------- COOKIE-ACK ---------------------
  ---------------- ASCONF_a; ASCONF_b -----------------&gt;

... where ASCONF_a equals ASCONF_b chunk (at least both serials
need to be equal), we panic an SCTP server!

The problem is that good-formed ASCONF chunks that we reply with
ASCONF_ACK chunks are cached per serial. Thus, when we receive a
same ASCONF chunk twice (e.g. through a lost ASCONF_ACK), we do
not need to process them again on the server side (that was the
idea, also proposed in the RFC). Instead, we know it was cached
and we just resend the cached chunk instead. So far, so good.

Where things get nasty is in SCTP's side effect interpreter, that
is, sctp_cmd_interpreter():

While incoming ASCONF_a (chunk = event_arg) is being marked
!end_of_packet and !singleton, and we have an association context,
we do not flush the outqueue the first time after processing the
ASCONF_ACK singleton chunk via SCTP_CMD_REPLY. Instead, we keep it
queued up, although we set local_cork to 1. Commit 2e3216cd54b1
changed the precedence, so that as long as we get bundled, incoming
chunks we try possible bundling on outgoing queue as well. Before
this commit, we would just flush the output queue.

Now, while ASCONF_a's ASCONF_ACK sits in the corked outq, we
continue to process the same ASCONF_b chunk from the packet. As
we have cached the previous ASCONF_ACK, we find it, grab it and
do another SCTP_CMD_REPLY command on it. So, effectively, we rip
the chunk-&gt;list pointers and requeue the same ASCONF_ACK chunk
another time. Since we process ASCONF_b, it's correctly marked
with end_of_packet and we enforce an uncork, and thus flush, thus
crashing the kernel.

Fix it by testing if the ASCONF_ACK is currently pending and if
that is the case, do not requeue it. When flushing the output
queue we may relink the chunk for preparing an outgoing packet,
but eventually unlink it when it's copied into the skb right
before transmission.

Joint work with Vlad Yasevich.

Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet")
Signed-off-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Signed-off-by: Vlad Yasevich &lt;vyasevich@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b69040d8e39f20d5215a03502a8e8b4c6ab78395 upstream.

When receiving a e.g. semi-good formed connection scan in the
form of ...

  -------------- INIT[ASCONF; ASCONF_ACK] -------------&gt;
  &lt;----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------
  -------------------- COOKIE-ECHO --------------------&gt;
  &lt;-------------------- COOKIE-ACK ---------------------
  ---------------- ASCONF_a; ASCONF_b -----------------&gt;

... where ASCONF_a equals ASCONF_b chunk (at least both serials
need to be equal), we panic an SCTP server!

The problem is that good-formed ASCONF chunks that we reply with
ASCONF_ACK chunks are cached per serial. Thus, when we receive a
same ASCONF chunk twice (e.g. through a lost ASCONF_ACK), we do
not need to process them again on the server side (that was the
idea, also proposed in the RFC). Instead, we know it was cached
and we just resend the cached chunk instead. So far, so good.

Where things get nasty is in SCTP's side effect interpreter, that
is, sctp_cmd_interpreter():

While incoming ASCONF_a (chunk = event_arg) is being marked
!end_of_packet and !singleton, and we have an association context,
we do not flush the outqueue the first time after processing the
ASCONF_ACK singleton chunk via SCTP_CMD_REPLY. Instead, we keep it
queued up, although we set local_cork to 1. Commit 2e3216cd54b1
changed the precedence, so that as long as we get bundled, incoming
chunks we try possible bundling on outgoing queue as well. Before
this commit, we would just flush the output queue.

Now, while ASCONF_a's ASCONF_ACK sits in the corked outq, we
continue to process the same ASCONF_b chunk from the packet. As
we have cached the previous ASCONF_ACK, we find it, grab it and
do another SCTP_CMD_REPLY command on it. So, effectively, we rip
the chunk-&gt;list pointers and requeue the same ASCONF_ACK chunk
another time. Since we process ASCONF_b, it's correctly marked
with end_of_packet and we enforce an uncork, and thus flush, thus
crashing the kernel.

Fix it by testing if the ASCONF_ACK is currently pending and if
that is the case, do not requeue it. When flushing the output
queue we may relink the chunk for preparing an outgoing packet,
but eventually unlink it when it's copied into the skb right
before transmission.

Joint work with Vlad Yasevich.

Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet")
Signed-off-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Signed-off-by: Vlad Yasevich &lt;vyasevich@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>vm: add VM_FAULT_SIGSEGV handling support</title>
<updated>2015-04-14T09:33:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-01-29T18:51:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a10ca0dbc2bcf3383fa42dcfeca055f7b5fe1106'/>
<id>a10ca0dbc2bcf3383fa42dcfeca055f7b5fe1106</id>
<content type='text'>
commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Tested-by: Jan Engelhardt &lt;jengelh@inai.de&gt;
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt; # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
[bwh: Backported to 3.2:
 - Adjust filenames, context
 - Drop arc, metag, nios2 and lustre changes
 - For sh, patch both 32-bit and 64-bit implementations to use goto bad_area
 - For s390, pass int_code and trans_exc_code as arguments to do_no_context()
   and do_sigsegv()]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
[lizf: Backported to 3.4:
 - adjust context in arch/power/mm/fault.c
 - apply the original change in upstream commit for s390]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
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commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Tested-by: Jan Engelhardt &lt;jengelh@inai.de&gt;
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt; # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
[bwh: Backported to 3.2:
 - Adjust filenames, context
 - Drop arc, metag, nios2 and lustre changes
 - For sh, patch both 32-bit and 64-bit implementations to use goto bad_area
 - For s390, pass int_code and trans_exc_code as arguments to do_no_context()
   and do_sigsegv()]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
[lizf: Backported to 3.4:
 - adjust context in arch/power/mm/fault.c
 - apply the original change in upstream commit for s390]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
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