user/sven/linux.git/include/linux, branch v4.14.154

kvm: Add helper function for creating VM worker threads

2019-11-12T18:19:08Z

commit c57c80467f90e5504c8df9ad3555d2c78800bf94 upstream. Add a function to create a kernel thread associated with a given VM. In particular, it ensures that the worker thread inherits the priority and cgroups of the calling thread. Signed-off-by: Junaid Shahid Signed-off-by: Paolo Bonzini Signed-off-by: Thomas Gleixner Signed-off-by: Paolo Bonzini Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

kvm: Convert kvm_lock to a mutex

2019-11-12T18:19:05Z

commit 0d9ce162cf46c99628cc5da9510b959c7976735b upstream. It doesn't seem as if there is any particular need for kvm_lock to be a spinlock, so convert the lock to a mutex so that sleepable functions (in particular cond_resched()) can be called while holding it. Signed-off-by: Junaid Shahid Signed-off-by: Paolo Bonzini Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

kvm: x86, powerpc: do not allow clearing largepages debugfs entry

2019-11-12T18:19:05Z

commit 833b45de69a6016c4b0cebe6765d526a31a81580 upstream. The largepages debugfs entry is incremented/decremented as shadow pages are created or destroyed. Clearing it will result in an underflow, which is harmless to KVM but ugly (and could be misinterpreted by tools that use debugfs information), so make this particular statistic read-only. Signed-off-by: Paolo Bonzini Signed-off-by: Thomas Gleixner Cc: kvm-ppc@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

cpu/speculation: Uninline and export CPU mitigations helpers

2019-11-12T18:19:04Z

commit 731dc9df975a5da21237a18c3384f811a7a41cc6 upstream. A kernel module may need to check the value of the "mitigations=" kernel command line parameter as part of its setup when the module needs to perform software mitigations for a CPU flaw. Uninline and export the helper functions surrounding the cpu_mitigations enum to allow for their usage from a module. Lastly, privatize the enum and cpu_mitigations variable since the value of cpu_mitigations can be checked with the exported helper functions. Signed-off-by: Tyler Hicks Signed-off-by: Paolo Bonzini Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

x86/bugs: Add ITLB_MULTIHIT bug infrastructure

2019-11-12T18:19:03Z

commit db4d30fbb71b47e4ecb11c4efa5d8aad4b03dfae upstream. Some processors may incur a machine check error possibly resulting in an unrecoverable CPU lockup when an instruction fetch encounters a TLB multi-hit in the instruction TLB. This can occur when the page size is changed along with either the physical address or cache type. The relevant erratum can be found here: https://bugzilla.kernel.org/show_bug.cgi?id=205195 There are other processors affected for which the erratum does not fully disclose the impact. This issue affects both bare-metal x86 page tables and EPT. It can be mitigated by either eliminating the use of large pages or by using careful TLB invalidations when changing the page size in the page tables. Just like Spectre, Meltdown, L1TF and MDS, a new bit has been allocated in MSR_IA32_ARCH_CAPABILITIES (PSCHANGE_MC_NO) and will be set on CPUs which are mitigated against this issue. Signed-off-by: Vineela Tummalapalli Co-developed-by: Pawan Gupta Signed-off-by: Pawan Gupta Signed-off-by: Paolo Bonzini Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

x86/speculation/taa: Add sysfs reporting for TSX Async Abort

2019-11-12T18:19:00Z

commit 6608b45ac5ecb56f9e171252229c39580cc85f0f upstream. Add the sysfs reporting file for TSX Async Abort. It exposes the vulnerability and the mitigation state similar to the existing files for the other hardware vulnerabilities. Sysfs file path is: /sys/devices/system/cpu/vulnerabilities/tsx_async_abort Signed-off-by: Pawan Gupta Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Tested-by: Neelima Krishnan Reviewed-by: Mark Gross Reviewed-by: Tony Luck Reviewed-by: Greg Kroah-Hartman Reviewed-by: Josh Poimboeuf Signed-off-by: Greg Kroah-Hartman

lib/scatterlist: Introduce sgl_alloc() and sgl_free()

2019-11-12T18:18:30Z

commit e80a0af4759a164214f02da157a3800753ce135f upstream. Many kernel drivers contain code that allocates and frees both a scatterlist and the pages that populate that scatterlist. Introduce functions in lib/scatterlist.c that perform these tasks instead of duplicating this functionality in multiple drivers. Only include these functions in the build if CONFIG_SGL_ALLOC=y to avoid that the kernel size increases if this functionality is not used. Signed-off-by: Bart Van Assche Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

mfd: palmas: Assign the right powerhold mask for tps65917

2019-11-12T18:18:19Z

commit 572ff4d560be3784205b224cd67d6715620092d7 upstream The powerhold mask for TPS65917 is different when comapred to the other palmas versions. Hence assign the right mask that enables power off of tps65917 pmic correctly. Signed-off-by: Keerthy Signed-off-by: Lee Jones Signed-off-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

mm: thp: handle page cache THP correctly in PageTransCompoundMap

2019-11-12T18:18:00Z

commit 169226f7e0d275c1879551f37484ef6683579a5c upstream. We have a usecase to use tmpfs as QEMU memory backend and we would like to take the advantage of THP as well. But, our test shows the EPT is not PMD mapped even though the underlying THP are PMD mapped on host. The number showed by /sys/kernel/debug/kvm/largepage is much less than the number of PMD mapped shmem pages as the below: 7f2778200000-7f2878200000 rw-s 00000000 00:14 262232 /dev/shm/qemu_back_mem.mem.Hz2hSf (deleted) Size: 4194304 kB [snip] AnonHugePages: 0 kB ShmemPmdMapped: 579584 kB [snip] Locked: 0 kB cat /sys/kernel/debug/kvm/largepages 12 And some benchmarks do worse than with anonymous THPs. By digging into the code we figured out that commit 127393fbe597 ("mm: thp: kvm: fix memory corruption in KVM with THP enabled") checks if there is a single PTE mapping on the page for anonymous THP when setting up EPT map. But the _mapcount < 0 check doesn't work for page cache THP since every subpage of page cache THP would get _mapcount inc'ed once it is PMD mapped, so PageTransCompoundMap() always returns false for page cache THP. This would prevent KVM from setting up PMD mapped EPT entry. So we need handle page cache THP correctly. However, when page cache THP's PMD gets split, kernel just remove the map instead of setting up PTE map like what anonymous THP does. Before KVM calls get_user_pages() the subpages may get PTE mapped even though it is still a THP since the page cache THP may be mapped by other processes at the mean time. Checking its _mapcount and whether the THP has PTE mapped or not. Although this may report some false negative cases (PTE mapped by other processes), it looks not trivial to make this accurate. With this fix /sys/kernel/debug/kvm/largepage would show reasonable pages are PMD mapped by EPT as the below: 7fbeaee00000-7fbfaee00000 rw-s 00000000 00:14 275464 /dev/shm/qemu_back_mem.mem.SKUvat (deleted) Size: 4194304 kB [snip] AnonHugePages: 0 kB ShmemPmdMapped: 557056 kB [snip] Locked: 0 kB cat /sys/kernel/debug/kvm/largepages 271 And the benchmarks are as same as anonymous THPs. [yang.shi@linux.alibaba.com: v4] Link: http://lkml.kernel.org/r/1571865575-42913-1-git-send-email-yang.shi@linux.alibaba.com Link: http://lkml.kernel.org/r/1571769577-89735-1-git-send-email-yang.shi@linux.alibaba.com Fixes: dd78fedde4b9 ("rmap: support file thp") Signed-off-by: Yang Shi Reported-by: Gang Deng Tested-by: Gang Deng Suggested-by: Hugh Dickins Acked-by: Kirill A. Shutemov Cc: Andrea Arcangeli Cc: Matthew Wilcox Cc: [4.8+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

net/flow_dissector: switch to siphash

2019-11-10T10:25:37Z

commit 55667441c84fa5e0911a0aac44fb059c15ba6da2 upstream. UDP IPv6 packets auto flowlabels are using a 32bit secret (static u32 hashrnd in net/core/flow_dissector.c) and apply jhash() over fields known by the receivers. Attackers can easily infer the 32bit secret and use this information to identify a device and/or user, since this 32bit secret is only set at boot time. Really, using jhash() to generate cookies sent on the wire is a serious security concern. Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be a dead end. Trying to periodically change the secret (like in sch_sfq.c) could change paths taken in the network for long lived flows. Let's switch to siphash, as we did in commit df453700e8d8 ("inet: switch IP ID generator to siphash") Using a cryptographically strong pseudo random function will solve this privacy issue and more generally remove other weak points in the stack. Packet schedulers using skb_get_hash_perturb() benefit from this change. Fixes: b56774163f99 ("ipv6: Enable auto flow labels by default") Fixes: 42240901f7c4 ("ipv6: Implement different admin modes for automatic flow labels") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Fixes: cb1ce2ef387b ("ipv6: Implement automatic flow label generation on transmit") Signed-off-by: Eric Dumazet Reported-by: Jonathan Berger Reported-by: Amit Klein Reported-by: Benny Pinkas Cc: Tom Herbert Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman