user/sven/linux.git/Documentation, branch v3.16.52

media: docs-rst: v4l: Fix sink compose selection target documentation

2017-11-26T13:50:14Z

commit 74dcb29a38e4419a8e4217caa7e35ccc1b31e5a4 upstream. The rectangle which the sink compose rectangle is related to is documented to be the source compose bounds rectangle. This is in obvious conflict with the ground rule of the format propagation (from sink to source). The reason behind this is that this was always supposed to be the sink compose bounds rectangle. Fix it. Fixes: 955f645aea04 ("[media] v4l: Add subdev selections documentation") Signed-off-by: Sakari Ailus Acked-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab [bwh: Backported to 3.16: adjust filename, context] Signed-off-by: Ben Hutchings

MODULE_DEVICE_TABLE: fix some callsites

2017-11-11T13:33:42Z

commit 0f989f749b51ec1fd94bb5a42f8ad10c8b9f73cb upstream. The patch "module: fix types of device tables aliases" newly requires that invocations of MODULE_DEVICE_TABLE(type, name); come *after* the definition of `name'. That is reasonable, but some drivers weren't doing this. Fix them. Cc: James Bottomley Cc: Andrey Ryabinin Cc: David Miller Cc: Hans Verkuil Acked-by: Mauro Carvalho Chehab Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman Signed-off-by: Arnd Bergmann Signed-off-by: Ben Hutchings

cpuset: PF_SPREAD_PAGE and PF_SPREAD_SLAB should be atomic flags

2017-10-12T14:28:22Z

commit 2ad654bc5e2b211e92f66da1d819e47d79a866f0 upstream. When we change cpuset.memory_spread_{page,slab}, cpuset will flip PF_SPREAD_{PAGE,SLAB} bit of tsk->flags for each task in that cpuset. This should be done using atomic bitops, but currently we don't, which is broken. Tetsuo reported a hard-to-reproduce kernel crash on RHEL6, which happened when one thread tried to clear PF_USED_MATH while at the same time another thread tried to flip PF_SPREAD_PAGE/PF_SPREAD_SLAB. They both operate on the same task. Here's the full report: https://lkml.org/lkml/2014/9/19/230 To fix this, we make PF_SPREAD_PAGE and PF_SPREAD_SLAB atomic flags. v4: - updated mm/slab.c. (Fengguang Wu) - updated Documentation. Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Miao Xie Cc: Kees Cook Fixes: 950592f7b991 ("cpusets: update tasks' page/slab spread flags in time") Reported-by: Tetsuo Handa Signed-off-by: Zefan Li Signed-off-by: Tejun Heo Signed-off-by: Ben Hutchings

Documentation: DMA API: fix a typo in a function name

2017-10-12T14:27:44Z

commit 6a08d83e4324fcb23994dfd481acedf49e37cc06 upstream. Correct the typo, the wrongly typed function does not exist. Fixes: 6c9c6d6301287e ("dma-debug: New interfaces to debug dma mapping errors") Signed-off-by: Wolfram Sang Signed-off-by: Jonathan Corbet Signed-off-by: Ben Hutchings

mm: larger stack guard gap, between vmas

2017-07-02T16:13:02Z

commit 1be7107fbe18eed3e319a6c3e83c78254b693acb upstream. Stack guard page is a useful feature to reduce a risk of stack smashing into a different mapping. We have been using a single page gap which is sufficient to prevent having stack adjacent to a different mapping. But this seems to be insufficient in the light of the stack usage in userspace. E.g. glibc uses as large as 64kB alloca() in many commonly used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX] which is 256kB or stack strings with MAX_ARG_STRLEN. This will become especially dangerous for suid binaries and the default no limit for the stack size limit because those applications can be tricked to consume a large portion of the stack and a single glibc call could jump over the guard page. These attacks are not theoretical, unfortunatelly. Make those attacks less probable by increasing the stack guard gap to 1MB (on systems with 4k pages; but make it depend on the page size because systems with larger base pages might cap stack allocations in the PAGE_SIZE units) which should cover larger alloca() and VLA stack allocations. It is obviously not a full fix because the problem is somehow inherent, but it should reduce attack space a lot. One could argue that the gap size should be configurable from userspace, but that can be done later when somebody finds that the new 1MB is wrong for some special case applications. For now, add a kernel command line option (stack_guard_gap) to specify the stack gap size (in page units). Implementation wise, first delete all the old code for stack guard page: because although we could get away with accounting one extra page in a stack vma, accounting a larger gap can break userspace - case in point, a program run with "ulimit -S -v 20000" failed when the 1MB gap was counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK and strict non-overcommit mode. Instead of keeping gap inside the stack vma, maintain the stack guard gap as a gap between vmas: using vm_start_gap() in place of vm_start (or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few places which need to respect the gap - mainly arch_get_unmapped_area(), and and the vma tree's subtree_gap support for that. Original-patch-by: Oleg Nesterov Original-patch-by: Michal Hocko Signed-off-by: Hugh Dickins Acked-by: Michal Hocko Tested-by: Helge Deller # parisc Signed-off-by: Linus Torvalds [Hugh Dickins: Backported to 3.16] Signed-off-by: Ben Hutchings

x86/platform/goldfish: Prevent unconditional loading

2017-06-05T20:17:09Z

commit 47512cfd0d7a8bd6ab71d01cd89fca19eb2093eb upstream. The goldfish platform code registers the platform device unconditionally which causes havoc in several ways if the goldfish_pdev_bus driver is enabled: - Access to the hardcoded physical memory region, which is either not available or contains stuff which is completely unrelated. - Prevents that the interrupt of the serial port can be requested - In case of a spurious interrupt it goes into a infinite loop in the interrupt handler of the pdev_bus driver (which needs to be fixed seperately). Add a 'goldfish' command line option to make the registration opt-in when the platform is compiled in. I'm seriously grumpy about this engineering trainwreck, which has seven SOBs from Intel developers for 50 lines of code. And none of them figured out that this is broken. Impressive fail! Fixes: ddd70cf93d78 ("goldfish: platform device for x86") Reported-by: Gabriel C Signed-off-by: Thomas Gleixner Acked-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings

i2c: i2c-mux-gpio: rename i2c-gpio-mux to i2c-mux-gpio

2017-06-05T20:17:06Z

commit 6b66a6f27e799d9441ef2c0b1e00913a6a070fa5 upstream. The rename did the wrong thing for this documentation file all those years ago. Fix that as well as the neglected rename of the platform data structure. Fixes: e7065e20d9a6 ("i2c: Rename last mux driver to standard pattern") Signed-off-by: Peter Rosin Signed-off-by: Wolfram Sang Signed-off-by: Ben Hutchings

netlink: remove mmapped netlink support

2017-04-04T21:21:56Z

commit d1b4c689d4130bcfd3532680b64db562300716b6 upstream. mmapped netlink has a number of unresolved issues: - TX zerocopy support had to be disabled more than a year ago via commit 4682a0358639b29cf ("netlink: Always copy on mmap TX.") because the content of the mmapped area can change after netlink attribute validation but before message processing. - RX support was implemented mainly to speed up nfqueue dumping packet payload to userspace. However, since commit ae08ce0021087a5d812d2 ("netfilter: nfnetlink_queue: zero copy support") we avoid one copy with the socket-based interface too (via the skb_zerocopy helper). The other problem is that skbs attached to mmaped netlink socket behave different from normal skbs: - they don't have a shinfo area, so all functions that use skb_shinfo() (e.g. skb_clone) cannot be used. - reserving headroom prevents userspace from seeing the content as it expects message to start at skb->head. See for instance commit aa3a022094fa ("netlink: not trim skb for mmaped socket when dump"). - skbs handed e.g. to netlink_ack must have non-NULL skb->sk, else we crash because it needs the sk to check if a tx ring is attached. Also not obvious, leads to non-intuitive bug fixes such as 7c7bdf359 ("netfilter: nfnetlink: use original skbuff when acking batches"). mmaped netlink also didn't play nicely with the skb_zerocopy helper used by nfqueue and openvswitch. Daniel Borkmann fixed this via commit 6bb0fef489f6 ("netlink, mmap: fix edge-case leakages in nf queue zero-copy")' but at the cost of also needing to provide remaining length to the allocation function. nfqueue also has problems when used with mmaped rx netlink: - mmaped netlink doesn't allow use of nfqueue batch verdict messages. Problem is that in the mmap case, the allocation time also determines the ordering in which the frame will be seen by userspace (A allocating before B means that A is located in earlier ring slot, but this also means that B might get a lower sequence number then A since seqno is decided later. To fix this we would need to extend the spinlocked region to also cover the allocation and message setup which isn't desirable. - nfqueue can now be configured to queue large (GSO) skbs to userspace. Queing GSO packets is faster than having to force a software segmentation in the kernel, so this is a desirable option. However, with a mmap based ring one has to use 64kb per ring slot element, else mmap has to fall back to the socket path (NL_MMAP_STATUS_COPY) for all large packets. To use the mmap interface, userspace not only has to probe for mmap netlink support, it also has to implement a recv/socket receive path in order to handle messages that exceed the size of an rx ring element. Cc: Daniel Borkmann Cc: Ken-ichirou MATSUZAWA Cc: Pablo Neira Ayuso Cc: Patrick McHardy Cc: Thomas Graf Signed-off-by: Florian Westphal Signed-off-by: David S. Miller [bwh: Backported to 3.16: deleted code and documentation is different in places] Signed-off-by: Ben Hutchings Cc: Shi Yuejie

KVM: PPC: Book3S HV: Save/restore XER in checkpointed register state

2017-03-16T02:26:24Z

commit 0d808df06a44200f52262b6eb72bcb6042f5a7c5 upstream. When switching from/to a guest that has a transaction in progress, we need to save/restore the checkpointed register state. Although XER is part of the CPU state that gets checkpointed, the code that does this saving and restoring doesn't save/restore XER. This fixes it by saving and restoring the XER. To allow userspace to read/write the checkpointed XER value, we also add a new ONE_REG specifier. The visible effect of this bug is that the guest may see its XER value being corrupted when it uses transactions. Fixes: e4e38121507a ("KVM: PPC: Book3S HV: Add transactional memory support") Fixes: 0a8eccefcb34 ("KVM: PPC: Book3S HV: Add missing code for transaction reclaim on guest exit") Signed-off-by: Paul Mackerras Reviewed-by: Thomas Huth Signed-off-by: Paul Mackerras [bwh: Backported to 3.16: adjust context, spacing] Signed-off-by: Ben Hutchings

ARM: dts: imx31: fix clock control module interrupts description

2017-03-16T02:26:18Z

commit 2e575cbc930901718cc18e084566ecbb9a4b5ebb upstream. The type of AVIC interrupt controller found on i.MX31 is one-cell, namely 31 for CCM DVFS and 53 for CCM, however for clock control module its interrupts are specified as 3-cells, fix it. Fixes: ef0e4a606fb6 ("ARM: mx31: Replace clk_register_clkdev with clock DT lookup") Acked-by: Rob Herring Signed-off-by: Vladimir Zapolskiy Signed-off-by: Shawn Guo Signed-off-by: Ben Hutchings