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2018-09-25i2c: i2c-qcom-geni: Properly handle DMA safe buffersStephen Boyd1-4/+18
We shouldn't attempt to DMA map the message buffers passed into this driver from the i2c core unless the message we're mapping have been properly setup for DMA. The i2c core indicates such a situation by setting the I2C_M_DMA_SAFE flag, so check for that flag before using DMA mode. We can also bounce the buffer if it isn't already mapped properly by using the i2c_get_dma_safe_msg_buf() APIs, so do that when we want to use DMA for a message. This fixes a problem where the kernel oopses cleaning pages for a buffer that's mapped into the vmalloc space. The pages are returned from request_firmware() and passed down directly to the i2c master to write to the i2c touchscreen device. Mapping vmalloc buffers with dma_map_single() won't work reliably, causing an oops like below: Unable to handle kernel paging request at virtual address ffffffc01391d000 ... Reported-by: Philip Chen <philipchen@chromium.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-09-23Linux 4.19-rc5v4.19-rc5Greg Kroah-Hartman1-1/+1
2018-09-22block: use nanosecond resolution for iostatOmar Sandoval5-11/+12
Klaus Kusche reported that the I/O busy time in /proc/diskstats was not updating properly on 4.18. This is because we started using ktime to track elapsed time, and we convert nanoseconds to jiffies when we update the partition counter. However, this gets rounded down, so any I/Os that take less than a jiffy are not accounted for. Previously in this case, the value of jiffies would sometimes increment while we were doing I/O, so at least some I/Os were accounted for. Let's convert the stats to use nanoseconds internally. We still report milliseconds as before, now more accurately than ever. The value is still truncated to 32 bits for backwards compatibility. Fixes: 522a777566f5 ("block: consolidate struct request timestamp fields") Cc: stable@vger.kernel.org Reported-by: Klaus Kusche <klaus.kusche@computerix.info> Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-20x86/mm: Expand static page table for fixmap spaceFeng Tang6-8/+42
We met a kernel panic when enabling earlycon, which is due to the fixmap address of earlycon is not statically setup. Currently the static fixmap setup in head_64.S only covers 2M virtual address space, while it actually could be in 4M space with different kernel configurations, e.g. when VSYSCALL emulation is disabled. So increase the static space to 4M for now by defining FIXMAP_PMD_NUM to 2, and add a build time check to ensure that the fixmap is covered by the initial static page tables. Fixes: 1ad83c858c7d ("x86_64,vsyscall: Make vsyscall emulation configurable") Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: kernel test robot <rong.a.chen@intel.com> Reviewed-by: Juergen Gross <jgross@suse.com> (Xen parts) Cc: H Peter Anvin <hpa@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andy Lutomirsky <luto@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180920025828.23699-1-feng.tang@intel.com
2018-09-20ocfs2: fix ocfs2 read block panicJunxiao Bi1-0/+1
While reading block, it is possible that io error return due to underlying storage issue, in this case, BH_NeedsValidate was left in the buffer head. Then when reading the very block next time, if it was already linked into journal, that will trigger the following panic. [203748.702517] kernel BUG at fs/ocfs2/buffer_head_io.c:342! [203748.702533] invalid opcode: 0000 [#1] SMP [203748.702561] Modules linked in: ocfs2 ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sunrpc dm_switch dm_queue_length dm_multipath bonding be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i iw_cxgb4 cxgb4 cxgb3i libcxgbi iw_cxgb3 cxgb3 mdio ib_iser rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ipmi_devintf iTCO_wdt iTCO_vendor_support dcdbas ipmi_ssif i2c_core ipmi_si ipmi_msghandler acpi_pad pcspkr sb_edac edac_core lpc_ich mfd_core shpchp sg tg3 ptp pps_core ext4 jbd2 mbcache2 sr_mod cdrom sd_mod ahci libahci megaraid_sas wmi dm_mirror dm_region_hash dm_log dm_mod [203748.703024] CPU: 7 PID: 38369 Comm: touch Not tainted 4.1.12-124.18.6.el6uek.x86_64 #2 [203748.703045] Hardware name: Dell Inc. PowerEdge R620/0PXXHP, BIOS 2.5.2 01/28/2015 [203748.703067] task: ffff880768139c00 ti: ffff88006ff48000 task.ti: ffff88006ff48000 [203748.703088] RIP: 0010:[<ffffffffa05e9f09>] [<ffffffffa05e9f09>] ocfs2_read_blocks+0x669/0x7f0 [ocfs2] [203748.703130] RSP: 0018:ffff88006ff4b818 EFLAGS: 00010206 [203748.703389] RAX: 0000000008620029 RBX: ffff88006ff4b910 RCX: 0000000000000000 [203748.703885] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00000000023079fe [203748.704382] RBP: ffff88006ff4b8d8 R08: 0000000000000000 R09: ffff8807578c25b0 [203748.704877] R10: 000000000f637376 R11: 000000003030322e R12: 0000000000000000 [203748.705373] R13: ffff88006ff4b910 R14: ffff880732fe38f0 R15: 0000000000000000 [203748.705871] FS: 00007f401992c700(0000) GS:ffff880bfebc0000(0000) knlGS:0000000000000000 [203748.706370] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [203748.706627] CR2: 00007f4019252440 CR3: 00000000a621e000 CR4: 0000000000060670 [203748.707124] Stack: [203748.707371] ffff88006ff4b828 ffffffffa0609f52 ffff88006ff4b838 0000000000000001 [203748.707885] 0000000000000000 0000000000000000 ffff880bf67c3800 ffffffffa05eca00 [203748.708399] 00000000023079ff ffffffff81c58b80 0000000000000000 0000000000000000 [203748.708915] Call Trace: [203748.709175] [<ffffffffa0609f52>] ? ocfs2_inode_cache_io_unlock+0x12/0x20 [ocfs2] [203748.709680] [<ffffffffa05eca00>] ? ocfs2_empty_dir_filldir+0x80/0x80 [ocfs2] [203748.710185] [<ffffffffa05ec0cb>] ocfs2_read_dir_block_direct+0x3b/0x200 [ocfs2] [203748.710691] [<ffffffffa05f0fbf>] ocfs2_prepare_dx_dir_for_insert.isra.57+0x19f/0xf60 [ocfs2] [203748.711204] [<ffffffffa065660f>] ? ocfs2_metadata_cache_io_unlock+0x1f/0x30 [ocfs2] [203748.711716] [<ffffffffa05f4f3a>] ocfs2_prepare_dir_for_insert+0x13a/0x890 [ocfs2] [203748.712227] [<ffffffffa05f442e>] ? ocfs2_check_dir_for_entry+0x8e/0x140 [ocfs2] [203748.712737] [<ffffffffa061b2f2>] ocfs2_mknod+0x4b2/0x1370 [ocfs2] [203748.713003] [<ffffffffa061c385>] ocfs2_create+0x65/0x170 [ocfs2] [203748.713263] [<ffffffff8121714b>] vfs_create+0xdb/0x150 [203748.713518] [<ffffffff8121b225>] do_last+0x815/0x1210 [203748.713772] [<ffffffff812192e9>] ? path_init+0xb9/0x450 [203748.714123] [<ffffffff8121bca0>] path_openat+0x80/0x600 [203748.714378] [<ffffffff811bcd45>] ? handle_pte_fault+0xd15/0x1620 [203748.714634] [<ffffffff8121d7ba>] do_filp_open+0x3a/0xb0 [203748.714888] [<ffffffff8122a767>] ? __alloc_fd+0xa7/0x130 [203748.715143] [<ffffffff81209ffc>] do_sys_open+0x12c/0x220 [203748.715403] [<ffffffff81026ddb>] ? syscall_trace_enter_phase1+0x11b/0x180 [203748.715668] [<ffffffff816f0c9f>] ? system_call_after_swapgs+0xe9/0x190 [203748.715928] [<ffffffff8120a10e>] SyS_open+0x1e/0x20 [203748.716184] [<ffffffff816f0d5e>] system_call_fastpath+0x18/0xd7 [203748.716440] Code: 00 00 48 8b 7b 08 48 83 c3 10 45 89 f8 44 89 e1 44 89 f2 4c 89 ee e8 07 06 11 e1 48 8b 03 48 85 c0 75 df 8b 5d c8 e9 4d fa ff ff <0f> 0b 48 8b 7d a0 e8 dc c6 06 00 48 b8 00 00 00 00 00 00 00 10 [203748.717505] RIP [<ffffffffa05e9f09>] ocfs2_read_blocks+0x669/0x7f0 [ocfs2] [203748.717775] RSP <ffff88006ff4b818> Joesph ever reported a similar panic. Link: https://oss.oracle.com/pipermail/ocfs2-devel/2013-May/008931.html Link: http://lkml.kernel.org/r/20180912063207.29484-1-junxiao.bi@oracle.com Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <jiangqi903@gmail.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Changwei Ge <ge.changwei@h3c.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20mm: slowly shrink slabs with a relatively small number of objectsRoman Gushchin1-0/+11
9092c71bb724 ("mm: use sc->priority for slab shrink targets") changed the way that the target slab pressure is calculated and made it priority-based: delta = freeable >> priority; delta *= 4; do_div(delta, shrinker->seeks); The problem is that on a default priority (which is 12) no pressure is applied at all, if the number of potentially reclaimable objects is less than 4096 (1<<12). This causes the last objects on slab caches of no longer used cgroups to (almost) never get reclaimed. It's obviously a waste of memory. It can be especially painful, if these stale objects are holding a reference to a dying cgroup. Slab LRU lists are reparented on memcg offlining, but corresponding objects are still holding a reference to the dying cgroup. If we don't scan these objects, the dying cgroup can't go away. Most likely, the parent cgroup hasn't any directly charged objects, only remaining objects from dying children cgroups. So it can easily hold a reference to hundreds of dying cgroups. If there are no big spikes in memory pressure, and new memory cgroups are created and destroyed periodically, this causes the number of dying cgroups grow steadily, causing a slow-ish and hard-to-detect memory "leak". It's not a real leak, as the memory can be eventually reclaimed, but it could not happen in a real life at all. I've seen hosts with a steadily climbing number of dying cgroups, which doesn't show any signs of a decline in months, despite the host is loaded with a production workload. It is an obvious waste of memory, and to prevent it, let's apply a minimal pressure even on small shrinker lists. E.g. if there are freeable objects, let's scan at least min(freeable, scan_batch) objects. This fix significantly improves a chance of a dying cgroup to be reclaimed, and together with some previous patches stops the steady growth of the dying cgroups number on some of our hosts. Link: http://lkml.kernel.org/r/20180905230759.12236-1-guro@fb.com Fixes: 9092c71bb724 ("mm: use sc->priority for slab shrink targets") Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Rik van Riel <riel@surriel.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20kernel/sys.c: remove duplicated includeYueHaibing1-3/+0
Link: http://lkml.kernel.org/r/20180821133424.18716-1-yuehaibing@huawei.com Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20mm: shmem.c: Correctly annotate new inodes for lockdepJoel Fernandes (Google)1-0/+2
Directories and inodes don't necessarily need to be in the same lockdep class. For ex, hugetlbfs splits them out too to prevent false positives in lockdep. Annotate correctly after new inode creation. If its a directory inode, it will be put into a different class. This should fix a lockdep splat reported by syzbot: > ====================================================== > WARNING: possible circular locking dependency detected > 4.18.0-rc8-next-20180810+ #36 Not tainted > ------------------------------------------------------ > syz-executor900/4483 is trying to acquire lock: > 00000000d2bfc8fe (&sb->s_type->i_mutex_key#9){++++}, at: inode_lock > include/linux/fs.h:765 [inline] > 00000000d2bfc8fe (&sb->s_type->i_mutex_key#9){++++}, at: > shmem_fallocate+0x18b/0x12e0 mm/shmem.c:2602 > > but task is already holding lock: > 0000000025208078 (ashmem_mutex){+.+.}, at: ashmem_shrink_scan+0xb4/0x630 > drivers/staging/android/ashmem.c:448 > > which lock already depends on the new lock. > > -> #2 (ashmem_mutex){+.+.}: > __mutex_lock_common kernel/locking/mutex.c:925 [inline] > __mutex_lock+0x171/0x1700 kernel/locking/mutex.c:1073 > mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 > ashmem_mmap+0x55/0x520 drivers/staging/android/ashmem.c:361 > call_mmap include/linux/fs.h:1844 [inline] > mmap_region+0xf27/0x1c50 mm/mmap.c:1762 > do_mmap+0xa10/0x1220 mm/mmap.c:1535 > do_mmap_pgoff include/linux/mm.h:2298 [inline] > vm_mmap_pgoff+0x213/0x2c0 mm/util.c:357 > ksys_mmap_pgoff+0x4da/0x660 mm/mmap.c:1585 > __do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline] > __se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline] > __x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > -> #1 (&mm->mmap_sem){++++}: > __might_fault+0x155/0x1e0 mm/memory.c:4568 > _copy_to_user+0x30/0x110 lib/usercopy.c:25 > copy_to_user include/linux/uaccess.h:155 [inline] > filldir+0x1ea/0x3a0 fs/readdir.c:196 > dir_emit_dot include/linux/fs.h:3464 [inline] > dir_emit_dots include/linux/fs.h:3475 [inline] > dcache_readdir+0x13a/0x620 fs/libfs.c:193 > iterate_dir+0x48b/0x5d0 fs/readdir.c:51 > __do_sys_getdents fs/readdir.c:231 [inline] > __se_sys_getdents fs/readdir.c:212 [inline] > __x64_sys_getdents+0x29f/0x510 fs/readdir.c:212 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > -> #0 (&sb->s_type->i_mutex_key#9){++++}: > lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924 > down_write+0x8f/0x130 kernel/locking/rwsem.c:70 > inode_lock include/linux/fs.h:765 [inline] > shmem_fallocate+0x18b/0x12e0 mm/shmem.c:2602 > ashmem_shrink_scan+0x236/0x630 drivers/staging/android/ashmem.c:455 > ashmem_ioctl+0x3ae/0x13a0 drivers/staging/android/ashmem.c:797 > vfs_ioctl fs/ioctl.c:46 [inline] > file_ioctl fs/ioctl.c:501 [inline] > do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 > ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 > __do_sys_ioctl fs/ioctl.c:709 [inline] > __se_sys_ioctl fs/ioctl.c:707 [inline] > __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > other info that might help us debug this: > > Chain exists of: > &sb->s_type->i_mutex_key#9 --> &mm->mmap_sem --> ashmem_mutex > > Possible unsafe locking scenario: > > CPU0 CPU1 > ---- ---- > lock(ashmem_mutex); > lock(&mm->mmap_sem); > lock(ashmem_mutex); > lock(&sb->s_type->i_mutex_key#9); > > *** DEADLOCK *** > > 1 lock held by syz-executor900/4483: > #0: 0000000025208078 (ashmem_mutex){+.+.}, at: > ashmem_shrink_scan+0xb4/0x630 drivers/staging/android/ashmem.c:448 Link: http://lkml.kernel.org/r/20180821231835.166639-1-joel@joelfernandes.org Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: NeilBrown <neilb@suse.com> Suggested-by: NeilBrown <neilb@suse.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Hugh Dickins <hughd@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20fs/proc/kcore.c: fix invalid memory access in multi-page read optimizationDominique Martinet1-0/+1
The 'm' kcore_list item could point to kclist_head, and it is incorrect to look at m->addr / m->size in this case. There is no choice but to run through the list of entries for every address if we did not find any entry in the previous iteration Reset 'm' to NULL in that case at Omar Sandoval's suggestion. [akpm@linux-foundation.org: add comment] Link: http://lkml.kernel.org/r/1536100702-28706-1-git-send-email-asmadeus@codewreck.org Fixes: bf991c2231117 ("proc/kcore: optimize multiple page reads") Signed-off-by: Dominique Martinet <asmadeus@codewreck.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Omar Sandoval <osandov@osandov.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: James Morse <james.morse@arm.com> Cc: Bhupesh Sharma <bhsharma@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20mm: disable deferred struct page for 32-bit archesPasha Tatashin1-0/+1
Deferred struct page init is needed only on systems with large amount of physical memory to improve boot performance. 32-bit systems do not benefit from this feature. Jiri reported a problem where deferred struct pages do not work well with x86-32: [ 0.035162] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes) [ 0.035725] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) [ 0.036269] Initializing CPU#0 [ 0.036513] Initializing HighMem for node 0 (00036ffe:0007ffe0) [ 0.038459] page:f6780000 is uninitialized and poisoned [ 0.038460] raw: ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff ffffffff [ 0.039509] page dumped because: VM_BUG_ON_PAGE(1 && PageCompound(page)) [ 0.040038] ------------[ cut here ]------------ [ 0.040399] kernel BUG at include/linux/page-flags.h:293! [ 0.040823] invalid opcode: 0000 [#1] SMP PTI [ 0.041166] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc1_pt_jiri #9 [ 0.041694] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014 [ 0.042496] EIP: free_highmem_page+0x64/0x80 [ 0.042839] Code: 13 46 d8 c1 e8 18 5d 83 e0 03 8d 04 c0 c1 e0 06 ff 80 ec 5f 44 d8 c3 8d b4 26 00 00 00 00 ba 08 65 28 d8 89 d8 e8 fc 71 02 00 <0f> 0b 8d 76 00 8d bc 27 00 00 00 00 ba d0 b1 26 d8 89 d8 e8 e4 71 [ 0.044338] EAX: 0000003c EBX: f6780000 ECX: 00000000 EDX: d856cbe8 [ 0.044868] ESI: 0007ffe0 EDI: d838df20 EBP: d838df00 ESP: d838defc [ 0.045372] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210086 [ 0.045913] CR0: 80050033 CR2: 00000000 CR3: 18556000 CR4: 00040690 [ 0.046413] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 0.046913] DR6: fffe0ff0 DR7: 00000400 [ 0.047220] Call Trace: [ 0.047419] add_highpages_with_active_regions+0xbd/0x10d [ 0.047854] set_highmem_pages_init+0x5b/0x71 [ 0.048202] mem_init+0x2b/0x1e8 [ 0.048460] start_kernel+0x1d2/0x425 [ 0.048757] i386_start_kernel+0x93/0x97 [ 0.049073] startup_32_smp+0x164/0x168 [ 0.049379] Modules linked in: [ 0.049626] ---[ end trace 337949378db0abbb ]--- We free highmem pages before their struct pages are initialized: mem_init() set_highmem_pages_init() add_highpages_with_active_regions() free_highmem_page() .. Access uninitialized struct page here.. Because there is no reason to have this feature on 32-bit systems, just disable it. Link: http://lkml.kernel.org/r/20180831150506.31246-1-pavel.tatashin@microsoft.com Fixes: 2e3ca40f03bb ("mm: relax deferred struct page requirements") Signed-off-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Reported-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20fork: report pid exhaustion correctlyKJ Tsanaktsidis1-1/+1
Make the clone and fork syscalls return EAGAIN when the limit on the number of pids /proc/sys/kernel/pid_max is exceeded. Currently, when the pid_max limit is exceeded, the kernel will return ENOSPC from the fork and clone syscalls. This is contrary to the documented behaviour, which explicitly calls out the pid_max case as one where EAGAIN should be returned. It also leads to really confusing error messages in userspace programs which will complain about a lack of disk space when they fail to create processes/threads for this reason. This error is being returned because alloc_pid() uses the idr api to find a new pid; when there are none available, idr_alloc_cyclic() returns -ENOSPC, and this is being propagated back to userspace. This behaviour has been broken before, and was explicitly fixed in commit 35f71bc0a09a ("fork: report pid reservation failure properly"), so I think -EAGAIN is definitely the right thing to return in this case. The current behaviour change dates from commit 95846ecf9dac ("pid: replace pid bitmap implementation with IDR AIP") and was I believe unintentional. This patch has no impact on the case where allocating a pid fails because the child reaper for the namespace is dead; that case will still return -ENOMEM. Link: http://lkml.kernel.org/r/20180903111016.46461-1-ktsanaktsidis@zendesk.com Fixes: 95846ecf9dac ("pid: replace pid bitmap implementation with IDR AIP") Signed-off-by: KJ Tsanaktsidis <ktsanaktsidis@zendesk.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Gargi Sharma <gs051095@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20MAINTAINERS: Add X86 MM entryThomas Gleixner1-0/+9
Dave, Andy and Peter are de facto overseing the mm parts of X86. Add an explicit maintainers entry. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@kernel.org>
2018-09-20x86/intel_rdt: Add Reinette as co-maintainer for RDTFenghua Yu1-0/+1
Reinette Chatre is doing great job on enabling pseudo-locking and other features in RDT. Add her as co-maintainer for RDT. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Reinette Chatre <reinette.chatre@intel.com> Cc: "H Peter Anvin" <hpa@zytor.com> Cc: "Tony Luck" <tony.luck@intel.com> Link: https://lkml.kernel.org/r/1537472228-221799-1-git-send-email-fenghua.yu@intel.com
2018-09-20Revert "ubifs: xattr: Don't operate on deleted inodes"Richard Weinberger1-24/+0
This reverts commit 11a6fc3dc743e22fb50f2196ec55bee5140d3c52. UBIFS wants to assert that xattr operations are only issued on files with positive link count. The said patch made this operations return -ENOENT for unlinked files such that the asserts will no longer trigger. This was wrong since xattr operations are perfectly fine on unlinked files. Instead the assertions need to be fixed/removed. Cc: <stable@vger.kernel.org> Fixes: 11a6fc3dc743 ("ubifs: xattr: Don't operate on deleted inodes") Reported-by: Koen Vandeputte <koen.vandeputte@ncentric.com> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-09-20ubifs: drop false positive assertionSascha Hauer1-1/+3
The following sequence triggers ubifs_assert(c, c->lst.taken_empty_lebs > 0); at the end of ubifs_remount_fs(): mount -t ubifs /dev/ubi0_0 /mnt echo 1 > /sys/kernel/debug/ubifs/ubi0_0/ro_error umount /mnt mount -t ubifs -o ro /dev/ubix_y /mnt mount -o remount,ro /mnt The resulting UBIFS assert failed in ubifs_remount_fs at 1878 (pid 161) is a false positive. In the case above c->lst.taken_empty_lebs has never been changed from its initial zero value. This will only happen when the deferred recovery is done. Fix this by doing the assertion only when recovery has been done already. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Richard Weinberger <richard@nod.at>
2018-09-20ubifs: Check for name being NULL while mountingRichard Weinberger1-0/+3
The requested device name can be NULL or an empty string. Check for that and refuse to continue. UBIFS has to do this manually since we cannot use mount_bdev(), which checks for this condition. Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system") Reported-by: syzbot+38bd0f7865e5c6379280@syzkaller.appspotmail.com Signed-off-by: Richard Weinberger <richard@nod.at>
2018-09-20KVM: nVMX: Fix bad cleanup on error of get/set nested state IOCTLsLiran Alon1-8/+14
The handlers of IOCTLs in kvm_arch_vcpu_ioctl() are expected to set their return value in "r" local var and break out of switch block when they encounter some error. This is because vcpu_load() is called before the switch block which have a proper cleanup of vcpu_put() afterwards. However, KVM_{GET,SET}_NESTED_STATE IOCTLs handlers just return immediately on error without performing above mentioned cleanup. Thus, change these handlers to behave as expected. Fixes: 8fcc4b5923af ("kvm: nVMX: Introduce KVM_CAP_NESTED_STATE") Reviewed-by: Mark Kanda <mark.kanda@oracle.com> Reviewed-by: Patrick Colp <patrick.colp@oracle.com> Signed-off-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20drm/amdkfd: Fix ATS capablity was not reported correctly on some APUsYong Zhao3-6/+29
Because CRAT_CU_FLAGS_IOMMU_PRESENT was not set in some BIOS crat, we need to workaround this. For future compatibility, we also overwrite the bit in capability according to the value of needs_iommu_device. Acked-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Yong Zhao <Yong.Zhao@amd.com> Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com> Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-09-20drm/amdkfd: Change the control stack MTYPE from UC to NC on GFX9Yong Zhao5-5/+10
CWSR fails on Raven if the control stack is MTYPE_UC, which is used for regular GART mappings. As a workaround we map it using MTYPE_NC. The MEC firmware expects the control stack at one page offset from the start of the MQD so it is part of the MQD allocation on GFXv9. AMDGPU added a memory allocation flag just for this purpose. Acked-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Yong Zhao <yong.zhao@amd.com> Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com> Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-09-20drm/amdgpu: Fix SDMA HQD destroy error on gfx_v7Amber Lin1-1/+1
A wrong register bit was examinated for checking SDMA status so it reports false failures. This typo only appears on gfx_v7. gfx_v8 checks the correct bit. Acked-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Amber Lin <Amber.Lin@amd.com> Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com> Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-09-20pinctrl: intel: Do pin translation in other GPIO operations as wellMika Westerberg1-48/+63
For some reason I thought GPIOLIB handles translation from GPIO ranges to pinctrl pins but it turns out not to be the case. This means that when GPIOs operations are performed for a pin controller having a custom GPIO base such as Cannon Lake and Ice Lake incorrect pin number gets used internally. Fix this in the same way we did for lock/unlock IRQ operations and translate the GPIO number to pin before using it. Fixes: a60eac3239f0 ("pinctrl: intel: Allow custom GPIO base for pad groups") Reported-by: Rajat Jain <rajatja@google.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Rajat Jain <rajatja@google.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-20floppy: Do not copy a kernel pointer to user memory in FDGETPRM ioctlAndy Whitcroft1-0/+3
The final field of a floppy_struct is the field "name", which is a pointer to a string in kernel memory. The kernel pointer should not be copied to user memory. The FDGETPRM ioctl copies a floppy_struct to user memory, including this "name" field. This pointer cannot be used by the user and it will leak a kernel address to user-space, which will reveal the location of kernel code and data and undermine KASLR protection. Model this code after the compat ioctl which copies the returned data to a previously cleared temporary structure on the stack (excluding the name pointer) and copy out to userspace from there. As we already have an inparam union with an appropriate member and that memory is already cleared even for read only calls make use of that as a temporary store. Based on an initial patch by Brian Belleville. CVE-2018-7755 Signed-off-by: Andy Whitcroft <apw@canonical.com> Broke up long line. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-20libata: mask swap internal and hardware tagJens Axboe1-2/+12
hen we're comparing the hardware completion mask passed in from the driver with the internal tag pending mask, we need to account for the fact that the internal tag is different from the hardware tag. If not, then we can end up either prematurely completing the internal tag (since it's not set in the hw mask), or simply flag an error: ata2: illegal qc_active transition (100000000->00000001) If the internal tag is set, then swap that with the hardware tag in this case before comparing with what the hardware reports. Fixes: 28361c403683 ("libata: add extra internal command") Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=201151 Cc: stable@vger.kernel.org Reported-by: Paul Sbarra <sbarra.paul@gmail.com> Tested-by: Paul Sbarra <sbarra.paul@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-20Compiler Attributes: naked can be sharedMiguel Ojeda2-8/+8
The naked attribute is supported by at least gcc >= 4.6 (for ARM, which is the only current user), gcc >= 8 (for x86), clang >= 3.1 and icc >= 13. See https://godbolt.org/z/350Dyc Therefore, move it out of compiler-gcc.h so that the definition is shared by all compilers. This also fixes Clang support for ARM32 --- 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive"). Fixes: 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Eli Friedman <efriedma@codeaurora.org> Cc: Christopher Li <sparse@chrisli.org> Cc: Kees Cook <keescook@chromium.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Joe Perches <joe@perches.com> Cc: Dominique Martinet <asmadeus@codewreck.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-sparse@vger.kernel.org Suggested-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Stefan Agner <stefan@agner.ch> Reviewed-by: Stefan Agner <stefan@agner.ch> Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20Compiler Attributes: naked was fixed in gcc 4.6Miguel Ojeda1-7/+1
Commit 9c695203a7dd ("compiler-gcc.h: gcc-4.5 needs noclone and noinline on __naked functions") added noinline and noclone as a workaround for a gcc 4.5 bug, which was resolved in 4.6.0. Since now the minimum gcc supported version is 4.6, we can clean it up. See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=44290 and https://godbolt.org/z/h6NMIL Fixes: 815f0ddb346c ("include/linux/compiler*.h: make compiler-*.h mutually exclusive") Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Eli Friedman <efriedma@codeaurora.org> Cc: Christopher Li <sparse@chrisli.org> Cc: Kees Cook <keescook@chromium.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Joe Perches <joe@perches.com> Cc: Dominique Martinet <asmadeus@codewreck.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-sparse@vger.kernel.org Tested-by: Stefan Agner <stefan@agner.ch> Reviewed-by: Stefan Agner <stefan@agner.ch> Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-20drm/vmwgfx: Fix buffer object evictionThomas Hellstrom1-1/+1
Commit 19be55701071 ("drm/ttm: add operation ctx to ttm_bo_validate v2") introduced a regression where the vmwgfx driver refused to evict a buffer that was still busy instead of waiting for it to become idle. Fix this. Cc: <stable@vger.kernel.org> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Christian König <christian.koenig@amd.com>
2018-09-20drm/vmwgfx: Don't impose STDU limits on framebuffer sizeDeepak Rawat2-35/+14
If framebuffers are larger, we create bounce surfaces that are within STDU limits. Signed-off-by: Deepak Rawat <drawat@vmware.com> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2018-09-20drm/vmwgfx: limit mode size for all display unit to texture_maxDeepak Rawat1-3/+7
For all display units, limit mode size exposed to texture_max_width/ height as this is the maximum framebuffer size that virtual device can create. Signed-off-by: Deepak Rawat <drawat@vmware.com> Reviewed-by: Sinclair Yeh <syeh@vmware.com> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2018-09-20drm/vmwgfx: limit screen size to stdu_max during check_modesetDeepak Rawat1-8/+22
For STDU individual screen target size is limited by SVGA_REG_SCREENTARGET_MAX_WIDTH/HEIGHT registers so add that limit during atomic check_modeset. An additional limit is placed in the update_layout ioctl to avoid requesting layouts that current user-space typically can't support. Also modified the comments to reflect current limitation on topology. Signed-off-by: Deepak Rawat <drawat@vmware.com> Reviewed-by: Sinclair Yeh <syeh@vmware.com> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2018-09-20drm/vmwgfx: don't check for old_crtc_state enable statusDeepak Rawat1-1/+1
During atomic check to prepare the new topology no need to check if old_crtc_state was enabled or not. This will cause atomic_check to fail because due to connector routing a crtc can be in atomic_state even if there was no change to enable status. Detected this issue with igt run. Signed-off-by: Deepak Rawat <drawat@vmware.com> Reviewed-by: Sinclair Yeh <syeh@vmware.com> Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
2018-09-20drm/amdgpu: add new polaris pci idAlex Deucher2-6/+9
Add new pci id. Reviewed-by: Rex Zhu <Rex.Zhu@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org
2018-09-20kvm: selftests: Add platform_info_testDrew Schmitt5-1/+206
Test guest access to MSR_PLATFORM_INFO when the capability is enabled or disabled. Signed-off-by: Drew Schmitt <dasch@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: x86: Control guest reads of MSR_PLATFORM_INFODrew Schmitt4-0/+22
Add KVM_CAP_MSR_PLATFORM_INFO so that userspace can disable guest access to reads of MSR_PLATFORM_INFO. Disabling access to reads of this MSR gives userspace the control to "expose" this platform-dependent information to guests in a clear way. As it exists today, guests that read this MSR would get unpopulated information if userspace hadn't already set it (and prior to this patch series, only the CPUID faulting information could have been populated). This existing interface could be confusing if guests don't handle the potential for incorrect/incomplete information gracefully (e.g. zero reported for base frequency). Signed-off-by: Drew Schmitt <dasch@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: x86: Turbo bits in MSR_PLATFORM_INFODrew Schmitt1-1/+0
Allow userspace to set turbo bits in MSR_PLATFORM_INFO. Previously, only the CPUID faulting bit was settable. But now any bit in MSR_PLATFORM_INFO would be settable. This can be used, for example, to convey frequency information about the platform on which the guest is running. Signed-off-by: Drew Schmitt <dasch@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20nVMX x86: Check VPID value on vmentry of L2 guestsKrish Sadhukhan1-0/+3
According to section "Checks on VMX Controls" in Intel SDM vol 3C, the following check needs to be enforced on vmentry of L2 guests: If the 'enable VPID' VM-execution control is 1, the value of the of the VPID VM-execution control field must not be 0000H. Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Reviewed-by: Mark Kanda <mark.kanda@oracle.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20nVMX x86: check posted-interrupt descriptor addresss on vmentry of L2Krish Sadhukhan1-1/+5
According to section "Checks on VMX Controls" in Intel SDM vol 3C, the following check needs to be enforced on vmentry of L2 guests: - Bits 5:0 of the posted-interrupt descriptor address are all 0. - The posted-interrupt descriptor address does not set any bits beyond the processor's physical-address width. Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Reviewed-by: Mark Kanda <mark.kanda@oracle.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: nVMX: Wake blocked vCPU in guest-mode if pending interrupt in virtual APICvLiran Alon3-1/+32
In case L1 do not intercept L2 HLT or enter L2 in HLT activity-state, it is possible for a vCPU to be blocked while it is in guest-mode. According to Intel SDM 26.6.5 Interrupt-Window Exiting and Virtual-Interrupt Delivery: "These events wake the logical processor if it just entered the HLT state because of a VM entry". Therefore, if L1 enters L2 in HLT activity-state and L2 has a pending deliverable interrupt in vmcs12->guest_intr_status.RVI, then the vCPU should be waken from the HLT state and injected with the interrupt. In addition, if while the vCPU is blocked (while it is in guest-mode), it receives a nested posted-interrupt, then the vCPU should also be waken and injected with the posted interrupt. To handle these cases, this patch enhances kvm_vcpu_has_events() to also check if there is a pending interrupt in L2 virtual APICv provided by L1. That is, it evaluates if there is a pending virtual interrupt for L2 by checking RVI[7:4] > VPPR[7:4] as specified in Intel SDM 29.2.1 Evaluation of Pending Interrupts. Note that this also handles the case of nested posted-interrupt by the fact RVI is updated in vmx_complete_nested_posted_interrupt() which is called from kvm_vcpu_check_block() -> kvm_arch_vcpu_runnable() -> kvm_vcpu_running() -> vmx_check_nested_events() -> vmx_complete_nested_posted_interrupt(). Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Signed-off-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: VMX: check nested state and CR4.VMXE against SMMPaolo Bonzini1-2/+11
VMX cannot be enabled under SMM, check it when CR4 is set and when nested virtualization state is restored. This should fix some WARNs reported by syzkaller, mostly around alloc_shadow_vmcs. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20kvm: x86: make kvm_{load|put}_guest_fpu() staticSebastian Andrzej Siewior2-25/+23
The functions kvm_load_guest_fpu() kvm_put_guest_fpu() are only used locally, make them static. This requires also that both functions are moved because they are used before their implementation. Those functions were exported (via EXPORT_SYMBOL) before commit e5bb40251a920 ("KVM: Drop kvm_{load,put}_guest_fpu() exports"). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20x86/hyper-v: rename ipi_arg_{ex,non_ex} structuresVitaly Kuznetsov2-11/+13
These structures are going to be used from KVM code so let's make their names reflect their Hyper-V origin. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Acked-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: VMX: use preemption timer to force immediate VMExitSean Christopherson4-2/+31
A VMX preemption timer value of '0' is guaranteed to cause a VMExit prior to the CPU executing any instructions in the guest. Use the preemption timer (if it's supported) to trigger immediate VMExit in place of the current method of sending a self-IPI. This ensures that pending VMExit injection to L1 occurs prior to executing any instructions in the guest (regardless of nesting level). When deferring VMExit injection, KVM generates an immediate VMExit from the (possibly nested) guest by sending itself an IPI. Because hardware interrupts are blocked prior to VMEnter and are unblocked (in hardware) after VMEnter, this results in taking a VMExit(INTR) before any guest instruction is executed. But, as this approach relies on the IPI being received before VMEnter executes, it only works as intended when KVM is running as L0. Because there are no architectural guarantees regarding when IPIs are delivered, when running nested the INTR may "arrive" long after L2 is running e.g. L0 KVM doesn't force an immediate switch to L1 to deliver an INTR. For the most part, this unintended delay is not an issue since the events being injected to L1 also do not have architectural guarantees regarding their timing. The notable exception is the VMX preemption timer[1], which is architecturally guaranteed to cause a VMExit prior to executing any instructions in the guest if the timer value is '0' at VMEnter. Specifically, the delay in injecting the VMExit causes the preemption timer KVM unit test to fail when run in a nested guest. Note: this approach is viable even on CPUs with a broken preemption timer, as broken in this context only means the timer counts at the wrong rate. There are no known errata affecting timer value of '0'. [1] I/O SMIs also have guarantees on when they arrive, but I have no idea if/how those are emulated in KVM. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> [Use a hook for SVM instead of leaving the default in x86.c - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: VMX: modify preemption timer bit only when arming timerSean Christopherson1-29/+32
Provide a singular location where the VMX preemption timer bit is set/cleared so that future usages of the preemption timer can ensure the VMCS bit is up-to-date without having to modify unrelated code paths. For example, the preemption timer can be used to force an immediate VMExit. Cache the status of the timer to avoid redundant VMREAD and VMWRITE, e.g. if the timer stays armed across multiple VMEnters/VMExits. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: VMX: immediately mark preemption timer expired only for zero valueSean Christopherson1-6/+8
A VMX preemption timer value of '0' at the time of VMEnter is architecturally guaranteed to cause a VMExit prior to the CPU executing any instructions in the guest. This architectural definition is in place to ensure that a previously expired timer is correctly recognized by the CPU as it is possible for the timer to reach zero and not trigger a VMexit due to a higher priority VMExit being signalled instead, e.g. a pending #DB that morphs into a VMExit. Whether by design or coincidence, commit f4124500c2c1 ("KVM: nVMX: Fully emulate preemption timer") special cased timer values of '0' and '1' to ensure prompt delivery of the VMExit. Unlike '0', a timer value of '1' has no has no architectural guarantees regarding when it is delivered. Modify the timer emulation to trigger immediate VMExit if and only if the timer value is '0', and document precisely why '0' is special. Do this even if calibration of the virtual TSC failed, i.e. VMExit will occur immediately regardless of the frequency of the timer. Making only '0' a special case gives KVM leeway to be more aggressive in ensuring the VMExit is injected prior to executing instructions in the nested guest, and also eliminates any ambiguity as to why '1' is a special case, e.g. why wasn't the threshold for a "short timeout" set to 10, 100, 1000, etc... Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: SVM: Switch to bitmap_zalloc()Andy Shevchenko1-3/+2
Switch to bitmap_zalloc() to show clearly what we are allocating. Besides that it returns pointer of bitmap type instead of opaque void *. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM/MMU: Fix comment in walk_shadow_page_lockless_end()Tianyu Lan1-1/+1
kvm_commit_zap_page() has been renamed to kvm_mmu_commit_zap_page() This patch is to fix the commit. Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20kvm: selftests: use -pthread instead of -lpthreadLei Yang1-1/+1
I run into the following error testing/selftests/kvm/dirty_log_test.c:285: undefined reference to `pthread_create' testing/selftests/kvm/dirty_log_test.c:297: undefined reference to `pthread_join' collect2: error: ld returned 1 exit status my gcc version is gcc version 4.8.4 "-pthread" would work everywhere Signed-off-by: Lei Yang <Lei.Yang@windriver.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: x86: don't reset root in kvm_mmu_setup()Wei Yang1-1/+6
Here is the code path which shows kvm_mmu_setup() is invoked after kvm_mmu_create(). Since kvm_mmu_setup() is only invoked in this code path, this means the root_hpa and prev_roots are guaranteed to be invalid. And it is not necessary to reset it again. kvm_vm_ioctl_create_vcpu() kvm_arch_vcpu_create() vmx_create_vcpu() kvm_vcpu_init() kvm_arch_vcpu_init() kvm_mmu_create() kvm_arch_vcpu_setup() kvm_mmu_setup() kvm_init_mmu() This patch set reset_roots to false in kmv_mmu_setup(). Fixes: 50c28f21d045dde8c52548f8482d456b3f0956f5 Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20kvm: mmu: Don't read PDPTEs when paging is not enabledJunaid Shahid1-2/+2
kvm should not attempt to read guest PDPTEs when CR0.PG = 0 and CR4.PAE = 1. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20x86/kvm/lapic: always disable MMIO interface in x2APIC modeVitaly Kuznetsov2-3/+20
When VMX is used with flexpriority disabled (because of no support or if disabled with module parameter) MMIO interface to lAPIC is still available in x2APIC mode while it shouldn't be (kvm-unit-tests): PASS: apic_disable: Local apic enabled in x2APIC mode PASS: apic_disable: CPUID.1H:EDX.APIC[bit 9] is set FAIL: apic_disable: *0xfee00030: 50014 The issue appears because we basically do nothing while switching to x2APIC mode when APIC access page is not used. apic_mmio_{read,write} only check if lAPIC is disabled before proceeding to actual write. When APIC access is virtualized we correctly manipulate with VMX controls in vmx_set_virtual_apic_mode() and we don't get vmexits from memory writes in x2APIC mode so there's no issue. Disabling MMIO interface seems to be easy. The question is: what do we do with these reads and writes? If we add apic_x2apic_mode() check to apic_mmio_in_range() and return -EOPNOTSUPP these reads and writes will go to userspace. When lAPIC is in kernel, Qemu uses this interface to inject MSIs only (see kvm_apic_mem_write() in hw/i386/kvm/apic.c). This somehow works with disabled lAPIC but when we're in xAPIC mode we will get a real injected MSI from every write to lAPIC. Not good. The simplest solution seems to be to just ignore writes to the region and return ~0 for all reads when we're in x2APIC mode. This is what this patch does. However, this approach is inconsistent with what currently happens when flexpriority is enabled: we allocate APIC access page and create KVM memory region so in x2APIC modes all reads and writes go to this pre-allocated page which is, btw, the same for all vCPUs. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-19xen: issue warning message when out of grant maptrack entriesJuergen Gross1-6/+21
When a driver domain (e.g. dom0) is running out of maptrack entries it can't map any more foreign domain pages. Instead of silently stalling the affected domUs issue a rate limited warning in this case in order to make it easier to detect that situation. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>