kernel/linux.git/include, branch v3.0.75

vm: add vm_iomap_memory() helper function

2013-04-26T04:23:49+00:00

commit b4cbb197c7e7a68dbad0d491242e3ca67420c13e upstream. Various drivers end up replicating the code to mmap() their memory buffers into user space, and our core memory remapping function may be very flexible but it is unnecessarily complicated for the common cases to use. Our internal VM uses pfn's ("page frame numbers") which simplifies things for the VM, and allows us to pass physical addresses around in a denser and more efficient format than passing a "phys_addr_t" around, and having to shift it up and down by the page size. But it just means that drivers end up doing that shifting instead at the interface level. It also means that drivers end up mucking around with internal VM things like the vma details (vm_pgoff, vm_start/end) way more than they really need to. So this just exports a function to map a certain physical memory range into user space (using a phys_addr_t based interface that is much more natural for a driver) and hides all the complexity from the driver. Some drivers will still end up tweaking the vm_page_prot details for things like prefetching or cacheability etc, but that's actually relevant to the driver, rather than caring about what the page offset of the mapping is into the particular IO memory region. Acked-by: Greg Kroah-Hartman Signed-off-by: Linus Torvalds

KVM: Allow cross page reads and writes from cached translations.

2013-04-26T04:23:48+00:00

commit 8f964525a121f2ff2df948dac908dcc65be21b5b upstream. This patch adds support for kvm_gfn_to_hva_cache_init functions for reads and writes that will cross a page. If the range falls within the same memslot, then this will be a fast operation. If the range is split between two memslots, then the slower kvm_read_guest and kvm_write_guest are used. Tested: Test against kvm_clock unit tests. Signed-off-by: Andrew Honig Signed-off-by: Gleb Natapov Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

spinlocks and preemption points need to be at least compiler barriers

2013-04-12T16:18:09+00:00

commit 386afc91144b36b42117b0092893f15bc8798a80 upstream. In UP and non-preempt respectively, the spinlocks and preemption disable/enable points are stubbed out entirely, because there is no regular code that can ever hit the kind of concurrency they are meant to protect against. However, while there is no regular code that can cause scheduling, we _do_ end up having some exceptional (literally!) code that can do so, and that we need to make sure does not ever get moved into the critical region by the compiler. In particular, get_user() and put_user() is generally implemented as inline asm statements (even if the inline asm may then make a call instruction to call out-of-line), and can obviously cause a page fault and IO as a result. If that inline asm has been scheduled into the middle of a preemption-safe (or spinlock-protected) code region, we obviously lose. Now, admittedly this is *very* unlikely to actually ever happen, and we've not seen examples of actual bugs related to this. But partly exactly because it's so hard to trigger and the resulting bug is so subtle, we should be extra careful to get this right. So make sure that even when preemption is disabled, and we don't have to generate any actual *code* to explicitly tell the system that we are in a preemption-disabled region, we need to at least tell the compiler not to move things around the critical region. This patch grew out of the same discussion that caused commits 79e5f05edcbf ("ARC: Add implicit compiler barrier to raw_local_irq* functions") and 3e2e0d2c222b ("tile: comment assumption about __insn_mtspr for ") to come about. Note for stable: use discretion when/if applying this. As mentioned, this bug may never have actually bitten anybody, and gcc may never have done the required code motion for it to possibly ever trigger in practice. Signed-off-by: Linus Torvalds Cc: Steven Rostedt Cc: Peter Zijlstra Signed-off-by: Greg Kroah-Hartman

libata: Set max sector to 65535 for Slimtype DVD A DS8A8SH drive

2013-04-12T16:18:09+00:00

commit a32450e127fc6e5ca6d958ceb3cfea4d30a00846 upstream. The Slimtype DVD A DS8A8SH drive locks up when max sector is smaller than 65535, and the blow backtrace is observed on locking up: INFO: task flush-8:32:1130 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. flush-8:32 D ffffffff8180cf60 0 1130 2 0x00000000 ffff880273aef618 0000000000000046 0000000000000005 ffff880273aee000 ffff880273aee000 ffff880273aeffd8 ffff880273aee010 ffff880273aee000 ffff880273aeffd8 ffff880273aee000 ffff88026e842ea0 ffff880274a10000 Call Trace: [] schedule+0x5d/0x70 [] io_schedule+0x8c/0xd0 [] get_request+0x731/0x7d0 [] ? cfq_allow_merge+0x50/0x90 [] ? wake_up_bit+0x40/0x40 [] ? bio_attempt_back_merge+0x33/0x110 [] blk_queue_bio+0x23a/0x3f0 [] generic_make_request+0xc6/0x120 [] submit_bio+0x138/0x160 [] ? bio_alloc_bioset+0x96/0x120 [] submit_bh+0x1f1/0x220 [] __block_write_full_page+0x228/0x340 [] ? attach_nobh_buffers+0xc0/0xc0 [] ? I_BDEV+0x10/0x10 [] ? I_BDEV+0x10/0x10 [] block_write_full_page_endio+0xe6/0x100 [] block_write_full_page+0x15/0x20 [] blkdev_writepage+0x18/0x20 [] __writepage+0x17/0x40 [] write_cache_pages+0x34a/0x4a0 [] ? set_page_dirty+0x70/0x70 [] generic_writepages+0x51/0x80 [] do_writepages+0x20/0x50 [] __writeback_single_inode+0xa6/0x2b0 [] writeback_sb_inodes+0x311/0x4d0 [] __writeback_inodes_wb+0x86/0xd0 [] wb_writeback+0x1a3/0x330 [] ? _raw_spin_lock_irqsave+0x3f/0x50 [] ? get_nr_inodes+0x52/0x70 [] wb_do_writeback+0x1dc/0x260 [] ? schedule_timeout+0x204/0x240 [] bdi_writeback_thread+0x102/0x2b0 [] ? wb_do_writeback+0x260/0x260 [] kthread+0xc0/0xd0 [] ? kthread_worker_fn+0x1b0/0x1b0 [] ret_from_fork+0x7c/0xb0 [] ? kthread_worker_fn+0x1b0/0x1b0 The above trace was triggered by "dd if=/dev/zero of=/dev/sr0 bs=2048 count=32768" It was previously working by accident, since another bug introduced by 4dce8ba94c7 (libata: Use 'bool' return value for ata_id_XXX) caused all drives to use maxsect=65535. Signed-off-by: Shan Hai Signed-off-by: Jeff Garzik Signed-off-by: Greg Kroah-Hartman

libata: Use integer return value for atapi_command_packet_set

2013-04-12T16:18:08+00:00

commit d8668fcb0b257d9fdcfbe5c172a99b8d85e1cd82 upstream. The function returns type of ATAPI drives so it should return integer value. The commit 4dce8ba94c7 (libata: Use 'bool' return value for ata_id_XXX) since v2.6.39 changed the type of return value from int to bool, the change would cause all of the ATAPI class drives to be treated as TYPE_TAPE and the max_sectors of the drives to be set to 65535 because of the commit f8d8e5799b7(libata: increase 128 KB / cmd limit for ATAPI tape drives), for the function would return true for all ATAPI class drives and the TYPE_TAPE is defined as 0x01. Signed-off-by: Shan Hai Signed-off-by: Jeff Garzik Signed-off-by: Greg Kroah-Hartman

thermal: shorten too long mcast group name

2013-04-05T17:16:53+00:00

[ Upstream commits 73214f5d9f33b79918b1f7babddd5c8af28dd23d and f1e79e208076ffe7bad97158275f1c572c04f5c7, the latter adds an assertion to genetlink to prevent this from happening again in the future. ] The original name is too long. Signed-off-by: Masatake YAMATO Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

KVM: Ensure all vcpus are consistent with in-kernel irqchip settings

2013-04-05T17:16:38+00:00

commit 3e515705a1f46beb1c942bb8043c16f8ac7b1e9e upstream. If some vcpus are created before KVM_CREATE_IRQCHIP, then irqchip_in_kernel() and vcpu->arch.apic will be inconsistent, leading to potential NULL pointer dereferences. Fix by: - ensuring that no vcpus are installed when KVM_CREATE_IRQCHIP is called - ensuring that a vcpu has an apic if it is installed after KVM_CREATE_IRQCHIP This is somewhat long winded because vcpu->arch.apic is created without kvm->lock held. Based on earlier patch by Michael Ellerman. Signed-off-by: Michael Ellerman Signed-off-by: Avi Kivity Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman

NFSv4: Fix an Oops in the NFSv4 getacl code

2013-04-05T17:16:38+00:00

commit 331818f1c468a24e581aedcbe52af799366a9dfe upstream. Commit bf118a342f10dafe44b14451a1392c3254629a1f (NFSv4: include bitmap in nfsv4 get acl data) introduces the 'acl_scratch' page for the case where we may need to decode multi-page data. However it fails to take into account the fact that the variable may be NULL (for the case where we're not doing multi-page decode), and it also attaches it to the encoding xdr_stream rather than the decoding one. The immediate result is an Oops in nfs4_xdr_enc_getacl due to the call to page_address() with a NULL page pointer. Signed-off-by: Trond Myklebust Cc: Andy Adamson Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman

NFSv4: include bitmap in nfsv4 get acl data

2013-04-05T17:16:38+00:00

commit bf118a342f10dafe44b14451a1392c3254629a1f upstream. The NFSv4 bitmap size is unbounded: a server can return an arbitrary sized bitmap in an FATTR4_WORD0_ACL request. Replace using the nfs4_fattr_bitmap_maxsz as a guess to the maximum bitmask returned by a server with the inclusion of the bitmap (xdr length plus bitmasks) and the acl data xdr length to the (cached) acl page data. This is a general solution to commit e5012d1f "NFSv4.1: update nfs4_fattr_bitmap_maxsz" and fixes hitting a BUG_ON in xdr_shrink_bufhead when getting ACLs. Fix a bug in decode_getacl that returned -EINVAL on ACLs > page when getxattr was called with a NULL buffer, preventing ACL > PAGE_SIZE from being retrieved. Signed-off-by: Andy Adamson Signed-off-by: Trond Myklebust Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman

signal: Define __ARCH_HAS_SA_RESTORER so we know whether to clear sa_restorer

2013-04-05T17:16:35+00:00

Vaguely based on upstream commit 574c4866e33d 'consolidate kernel-side struct sigaction declarations'. flush_signal_handlers() needs to know whether sigaction::sa_restorer is defined, not whether SA_RESTORER is defined. Define the __ARCH_HAS_SA_RESTORER macro to indicate this. Signed-off-by: Ben Hutchings Cc: Al Viro Signed-off-by: Greg Kroah-Hartman