user/sven/linux.git/include, branch v3.2.67

vm: add VM_FAULT_SIGSEGV handling support

2015-02-20T00:49:40Z

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 Tested-by: Jan Engelhardt Acked-by: Heiko Carstens # "s390 still compiles and boots" Cc: linux-arch@vger.kernel.org Signed-off-by: Linus Torvalds [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

usb-core bInterval quirk

2015-02-20T00:49:39Z

commit cd83ce9e6195aa3ea15ab4db92892802c20df5d0 upstream. This patch adds a usb quirk to support devices with interupt endpoints and bInterval values expressed as microframes. The quirk causes the parse endpoint function to modify the reported bInterval to a standards conforming value. There is currently code in the endpoint parser that checks for bIntervals that are outside of the valid range (1-16 for USB 2+ high speed and super speed interupt endpoints). In this case, the code assumes the bInterval is being reported in 1ms frames. As well, the correction is only applied if the original bInterval value is out of the 1-16 range. With this quirk applied to the device, the bInterval will be accurately adjusted from microframes to an exponent. Signed-off-by: James P Michels III Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings

libata: allow sata_sil24 to opt-out of tag ordered submission

2015-02-20T00:49:38Z

commit 72dd299d5039a336493993dcc63413cf31d0e662 upstream. Ronny reports: https://bugzilla.kernel.org/show_bug.cgi?id=87101 "Since commit 8a4aeec8d "libata/ahci: accommodate tag ordered controllers" the access to the harddisk on the first SATA-port is failing on its first access. The access to the harddisk on the second port is working normal. When reverting the above commit, access to both harddisks is working fine again." Maintain tag ordered submission as the default, but allow sata_sil24 to continue with the old behavior. Cc: Tejun Heo Reported-by: Ronny Hegewald Signed-off-by: Dan Williams Signed-off-by: Tejun Heo Signed-off-by: Ben Hutchings

driver core: Introduce device_create_groups

2015-02-20T00:49:37Z

commit 39ef311204941ddd01ea2950d6220c8ccc710d15 upstream. device_create_groups lets callers create devices as well as associated sysfs attributes with a single call. This avoids race conditions seen if sysfs attributes on new devices are created later. [fixed up comment block placement and add checks for printk buffer formats - gregkh] Signed-off-by: Guenter Roeck Cc: Jean Delvare Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings

sysfs.h: add ATTRIBUTE_GROUPS() macro

2015-02-20T00:49:37Z

commit f2f37f58b1b933b06d6d84e80a31a1b500fb0db2 upstream. To make it easier for driver subsystems to work with attribute groups, create the ATTRIBUTE_GROUPS macro to remove some of the repetitive typing for the most common use for attribute groups. Reviewed-by: Guenter Roeck Tested-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings

crypto: prefix module autoloading with "crypto-"

2015-02-20T00:49:36Z

commit 5d26a105b5a73e5635eae0629b42fa0a90e07b7b upstream. This prefixes all crypto module loading with "crypto-" so we never run the risk of exposing module auto-loading to userspace via a crypto API, as demonstrated by Mathias Krause: https://lkml.org/lkml/2013/3/4/70 Signed-off-by: Kees Cook Signed-off-by: Herbert Xu [bwh: Backported to 3.2: - Adjust filenames - Drop changes to algorithms and drivers we don't have - Add aliases to generic C implementations that didn't need them before] Signed-off-by: Ben Hutchings

mm: protect set_page_dirty() from ongoing truncation

2015-02-20T00:49:35Z

commit 2d6d7f98284648c5ed113fe22a132148950b140f upstream. Tejun, while reviewing the code, spotted the following race condition between the dirtying and truncation of a page: __set_page_dirty_nobuffers() __delete_from_page_cache() if (TestSetPageDirty(page)) page->mapping = NULL if (PageDirty()) dec_zone_page_state(page, NR_FILE_DIRTY); dec_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE); if (page->mapping) account_page_dirtied(page) __inc_zone_page_state(page, NR_FILE_DIRTY); __inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE); which results in an imbalance of NR_FILE_DIRTY and BDI_RECLAIMABLE. Dirtiers usually lock out truncation, either by holding the page lock directly, or in case of zap_pte_range(), by pinning the mapcount with the page table lock held. The notable exception to this rule, though, is do_wp_page(), for which this race exists. However, do_wp_page() already waits for a locked page to unlock before setting the dirty bit, in order to prevent a race where clear_page_dirty() misses the page bit in the presence of dirty ptes. Upgrade that wait to a fully locked set_page_dirty() to also cover the situation explained above. Afterwards, the code in set_page_dirty() dealing with a truncation race is no longer needed. Remove it. Reported-by: Tejun Heo Signed-off-by: Johannes Weiner Acked-by: Kirill A. Shutemov Reviewed-by: Jan Kara Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [bwh: Backported to 3.2: - Adjust context - Use VM_BUG_ON() rather than VM_BUG_ON_PAGE()] Signed-off-by: Ben Hutchings

mm: remove unused arg of set_page_dirty_balance()

2015-02-20T00:49:35Z

commit ed6d7c8e578331cad594ee70d60e2e146b5dce7b upstream. There's only one caller of set_page_dirty_balance() and that will call it with page_mkwrite == 0. The page_mkwrite argument was unused since commit b827e496c893 "mm: close page_mkwrite races". Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings

mm: prevent endless growth of anon_vma hierarchy

2015-02-20T00:49:35Z

commit 7a3ef208e662f4b63d43a23f61a64a129c525bbc upstream. Constantly forking task causes unlimited grow of anon_vma chain. Each next child allocates new level of anon_vmas and links vma to all previous levels because pages might be inherited from any level. This patch adds heuristic which decides to reuse existing anon_vma instead of forking new one. It adds counter anon_vma->degree which counts linked vmas and directly descending anon_vmas and reuses anon_vma if counter is lower than two. As a result each anon_vma has either vma or at least two descending anon_vmas. In such trees half of nodes are leafs with alive vmas, thus count of anon_vmas is no more than two times bigger than count of vmas. This heuristic reuses anon_vmas as few as possible because each reuse adds false aliasing among vmas and rmap walker ought to scan more ptes when it searches where page is might be mapped. Link: http://lkml.kernel.org/r/20120816024610.GA5350@evergreen.ssec.wisc.edu Fixes: 5beb49305251 ("mm: change anon_vma linking to fix multi-process server scalability issue") [akpm@linux-foundation.org: fix typo, per Rik] Signed-off-by: Konstantin Khlebnikov Reported-by: Daniel Forrest Tested-by: Michal Hocko Tested-by: Jerome Marchand Reviewed-by: Michal Hocko Reviewed-by: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings

time: settimeofday: Validate the values of tv from user

2015-02-20T00:49:34Z

commit 6ada1fc0e1c4775de0e043e1bd3ae9d065491aa5 upstream. An unvalidated user input is multiplied by a constant, which can result in an undefined behaviour for large values. While this is validated later, we should avoid triggering undefined behaviour. Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Sasha Levin [jstultz: include trivial milisecond->microsecond correction noticed by Andy] Signed-off-by: John Stultz [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings