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* bpf: fix hashmap extra_elems logicAlexei Starovoitov2017-03-221-3/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In both kmalloc and prealloc mode the bpf_map_update_elem() is using per-cpu extra_elems to do atomic update when the map is full. There are two issues with it. The logic can be misused, since it allows max_entries+num_cpus elements to be present in the map. And alloc_extra_elems() at map creation time can fail percpu alloc for large map values with a warn: WARNING: CPU: 3 PID: 2752 at ../mm/percpu.c:892 pcpu_alloc+0x119/0xa60 illegal size (32824) or align (8) for percpu allocation The fixes for both of these issues are different for kmalloc and prealloc modes. For prealloc mode allocate extra num_possible_cpus elements and store their pointers into extra_elems array instead of actual elements. Hence we can use these hidden(spare) elements not only when the map is full but during bpf_map_update_elem() that replaces existing element too. That also improves performance, since pcpu_freelist_pop/push is avoided. Unfortunately this approach cannot be used for kmalloc mode which needs to kfree elements after rcu grace period. Therefore switch it back to normal kmalloc even when full and old element exists like it was prior to commit 6c9059817432 ("bpf: pre-allocate hash map elements"). Add tests to check for over max_entries and large map values. Reported-by: Dave Jones <davej@codemonkey.org.uk> Fixes: 6c9059817432 ("bpf: pre-allocate hash map elements") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* selftests/bpf: fix broken build, take 2Zi Shen Lim2017-03-211-9/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge of 'linux-kselftest-4.11-rc1': 1. Partially removed use of 'test_objs' target, breaking force rebuild of BPFOBJ, introduced in commit d498f8719a09 ("bpf: Rebuild bpf.o for any dependency update"). Update target so dependency on BPFOBJ is restored. 2. Introduced commit 2047f1d8ba28 ("selftests: Fix the .c linking rule") which fixes order of LDLIBS. Commit d02d8986a768 ("bpf: Always test unprivileged programs") added libcap dependency into CFLAGS. Use LDLIBS instead to fix linking of test_verifier. 3. Introduced commit d83c3ba0b926 ("selftests: Fix selftests build to just build, not run tests"). Reordering the Makefile allows us to remove the 'all' target. Tested both: selftests/bpf$ make and selftests$ make TARGETS=bpf on Ubuntu 16.04.2. Signed-off-by: Zi Shen Lim <zlim.lnx@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2017-03-142-1/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking fixes from David Miller: 1) Ensure that mtu is at least IPV6_MIN_MTU in ipv6 VTI tunnel driver, from Steffen Klassert. 2) Fix crashes when user tries to get_next_key on an LPM bpf map, from Alexei Starovoitov. 3) Fix detection of VLAN fitlering feature for bnx2x VF devices, from Michal Schmidt. 4) We can get a divide by zero when TCP socket are morphed into listening state, fix from Eric Dumazet. 5) Fix socket refcounting bugs in skb_complete_wifi_ack() and skb_complete_tx_timestamp(). From Eric Dumazet. 6) Use after free in dccp_feat_activate_values(), also from Eric Dumazet. 7) Like bonding team needs to use ETH_MAX_MTU as netdev->max_mtu, from Jarod Wilson. 8) Fix use after free in vrf_xmit(), from David Ahern. 9) Don't do UDP Fragmentation Offload on IPComp ipsec packets, from Alexey Kodanev. 10) Properly check napi_complete_done() return value in order to decide whether to re-enable IRQs or not in amd-xgbe driver, from Thomas Lendacky. 11) Fix double free of hwmon device in marvell phy driver, from Andrew Lunn. 12) Don't crash on malformed netlink attributes in act_connmark, from Etienne Noss. 13) Don't remove routes with a higher metric in ipv6 ECMP route replace, from Sabrina Dubroca. 14) Don't write into a cloned SKB in ipv6 fragmentation handling, from Florian Westphal. 15) Fix routing redirect races in dccp and tcp, basically the ICMP handler can't modify the socket's cached route in it's locked by the user at this moment. From Jon Maxwell. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (108 commits) qed: Enable iSCSI Out-of-Order qed: Correct out-of-bound access in OOO history qed: Fix interrupt flags on Rx LL2 qed: Free previous connections when releasing iSCSI qed: Fix mapping leak on LL2 rx flow qed: Prevent creation of too-big u32-chains qed: Align CIDs according to DORQ requirement mlxsw: reg: Fix SPVMLR max record count mlxsw: reg: Fix SPVM max record count net: Resend IGMP memberships upon peer notification. dccp: fix memory leak during tear-down of unsuccessful connection request tun: fix premature POLLOUT notification on tun devices dccp/tcp: fix routing redirect race ucc/hdlc: fix two little issue vxlan: fix ovs support net: use net->count to check whether a netns is alive or not bridge: drop netfilter fake rtable unconditionally ipv6: avoid write to a possibly cloned skb net: wimax/i2400m: fix NULL-deref at probe isdn/gigaset: fix NULL-deref at probe ...
| * selftests/bpf: fix broken buildAlexei Starovoitov2017-03-122-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | Recent merge of 'linux-kselftest-4.11-rc1' tree broke bpf test build. None of the tests were building and test_verifier.c had tons of compiler errors. Fix it and add #ifdef CAP_IS_SUPPORTED to support old versions of libcap. Tested on centos 6.8 and 7 Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge tag 'powerpc-4.11-4' of ↵Linus Torvalds2017-03-131-24/+24
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull some more powerpc fixes from Michael Ellerman: "The main item is the addition of the Power9 Machine Check handler. This was delayed to make sure some details were correct, and is as minimal as possible. The rest is small fixes, two for the Power9 PMU, two dealing with obscure toolchain problems, two for the PowerNV IOMMU code (used by VFIO), and one to fix a crash on 32-bit machines with macio devices due to missing dma_ops. Thanks to: Alexey Kardashevskiy, Cyril Bur, Larry Finger, Madhavan Srinivasan, Nicholas Piggin" * tag 'powerpc-4.11-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64s: POWER9 machine check handler powerpc/64s: allow machine check handler to set severity and initiator powerpc/64s: fix handling of non-synchronous machine checks powerpc/pmac: Fix crash in dma-mapping.h with NULL dma_ops powerpc/powernv/ioda2: Update iommu table base on ownership change powerpc/powernv/ioda2: Gracefully fail if too many TCE levels requested selftests/powerpc: Replace stxvx and lxvx with stxvd2x/lxvd2x powerpc/perf: Handle sdar_mode for marked event in power9 powerpc/perf: Fix perf_get_data_addr() for power9 DD1 powerpc/boot: Fix zImage TOC alignment
| * | selftests/powerpc: Replace stxvx and lxvx with stxvd2x/lxvd2xCyril Bur2017-03-091-24/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On POWER8 (ISA 2.07) lxvx and stxvx are defined to be extended mnemonics of lxvd2x and stxvd2x. For POWER9 (ISA 3.0) the HW architects in their infinite wisdom made lxvx and stxvx instructions in their own right. POWER9 aware GCC will use the POWER9 instruction for lxvx and stxvx causing these selftests to fail on POWER8. Further compounding the issue, because of the way -mvsx works it will cause the power9 instructions to be used regardless of -mcpu=power8 to GCC or -mpower8 to AS. The safest way to address the problem for now is to not use the extended mnemonic. We don't care how the CPU loads the values from memory since the tests only performs register comparisons, so using stdvd2x/lxvd2x does not impact the test. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Acked-by: Balbir Singh<bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | userfaultfd: selftest: vm: allow to build in vm/ directoryAndrea Arcangeli2017-03-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | linux/tools/testing/selftests/vm $ make gcc -Wall -I ../../../../usr/include compaction_test.c -lrt -o /compaction_test /usr/lib/gcc/x86_64-pc-linux-gnu/4.9.4/../../../../x86_64-pc-linux-gnu/bin/ld: cannot open output file /compaction_test: Permission denied collect2: error: ld returned 1 exit status make: *** [../lib.mk:54: /compaction_test] Error 1 Since commit a8ba798bc8ec ("selftests: enable O and KBUILD_OUTPUT") selftests/vm build fails if run from the "selftests/vm" directory, but it works in the selftests/ directory. It's quicker to be able to do a local vm-only build after a tree wipe and this patch allows for it again. Link: http://lkml.kernel.org/r/20170302173738.18994-4-aarcange@redhat.com Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge tag 'ktest-v4.11-rc1' of ↵Linus Torvalds2017-03-081-8/+13
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest Pull ktest fixes from Steven Rostedt: "Greg Kroah-Hartman reported to me that the ktest of v4.11-rc1 locked up in an infinite loop while doing the make mrproper. Looking into the cause I noticed that a recent update to the function run_command (used for running all shell commands, including "make mrproper") changed the internal loop to use the function wait_for_input. The wait_for_input function uses select to look at two file descriptors. One is the file descriptor of the command it is running, the other is STDIN. The STDIN check was not checking the return status of the sysread call, and was also just writing a lot of data into syswrite without regard to the size of the data read. Changing the code to check the return status of sysread, and also to still process the passed in descriptor data without looping back to the select fixed Greg's problem. While looking at this code I also realized that the loop did not honor the timeout if STDIN always had input (or for some reason return error). this could prevent wait_for_input to timeout on the file descriptor it is suppose to be waiting for. That is fixed too" * tag 'ktest-v4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest: ktest: Make sure wait_for_input does honor the timeout ktest: Fix while loop in wait_for_input
| * | | ktest: Make sure wait_for_input does honor the timeoutSteven Rostedt (VMware)2017-03-081-7/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function wait_for_input takes in a timeout, and even has a default timeout. But if for some reason the STDIN descriptor keeps sending in data, the function will never time out. The timout is to wait for the data from the passed in file descriptor, not for STDIN. Adding a test in the case where there's no data from the passed in file descriptor that checks to see if the timeout passed, will ensure that it will timeout properly even if there's input in STDIN. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * | | ktest: Fix while loop in wait_for_inputSteven Rostedt (VMware)2017-03-081-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The run_command function was changed to use the wait_for_input function to allow having a timeout if the command to run takes too much time. There was a bug in the wait_for_input where it could end up going into an infinite loop. There's two issues here. One is that the return value of the sysread wasn't used for the write (to write a proper size), and that it should continue processing the passed in file descriptor too even if there was input. There was no check for error, if for some reason STDIN returned an error, the function would go into an infinite loop and never exit. Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Tested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 6e98d1b4415f ("ktest: Add timeout to ssh command") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | | | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2017-03-074-8/+18
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes and minor updates all over the place: - an SGI/UV fix - a defconfig update - a build warning fix - move the boot_params file to the arch location in debugfs - a pkeys fix - selftests fix - boot message fixes - sparse fixes - a resume warning fix - ioapic hotplug fixes - reboot quirks ... plus various minor cleanups" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/build/x86_64_defconfig: Enable CONFIG_R8169 x86/reboot/quirks: Add ASUS EeeBook X205TA/W reboot quirk x86/hpet: Prevent might sleep splat on resume x86/boot: Correct setup_header.start_sys name x86/purgatory: Fix sparse warning, symbol not declared x86/purgatory: Make functions and variables static x86/events: Remove last remnants of old filenames x86/pkeys: Check against max pkey to avoid overflows x86/ioapic: Split IOAPIC hot-removal into two steps x86/PCI: Implement pcibios_release_device to release IRQ from IOAPIC x86/intel_rdt: Remove duplicate inclusion of linux/cpu.h x86/vmware: Remove duplicate inclusion of asm/timer.h x86/hyperv: Hide unused label x86/reboot/quirks: Add ASUS EeeBook X205TA reboot quirk x86/platform/uv/BAU: Fix HUB errors by remove initial write to sw-ack register x86/selftests: Add clobbers for int80 on x86_64 x86/apic: Simplify enable_IR_x2apic(), remove try_to_enable_IR() x86/apic: Fix a warning message in logical CPU IDs allocation x86/kdebugfs: Move boot params hierarchy under (debugfs)/x86/
| * | | | x86/selftests: Add clobbers for int80 on x86_64Dmitry Safonov2017-03-014-8/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kernel erases R8..R11 registers prior returning to userspace from int80: https://lkml.org/lkml/2009/10/1/164 GCC can reuse these registers and doesn't expect them to change during syscall invocation. I met this kind of bug in CRIU once GCC 6.1 and CLANG stored local variables in those registers and the kernel zerofied them during syscall: https://github.com/xemul/criu/commit/990d33f1a1cdd17bca6c2eb059ab3be2564f7fa2 By that reason I suggest to add those registers to clobbers in selftests. Also, as noted by Andy - removed unneeded clobber for flags in INT $0x80 inline asm. Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: 0x7f454c46@gmail.com Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kselftest@vger.kernel.org Link: http://lkml.kernel.org/r/20170213101336.20486-1-dsafonov@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | Merge branch 'idr-4.11' of git://git.infradead.org/users/willy/linux-daxLinus Torvalds2017-03-076-16/+281
|\ \ \ \ \ | |_|_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull idr fix (and new tests) from Matthew Wilcox: "One urgent patch in here; freeing the correct IDA bitmap. Everything else is changes to the test suite" * 'idr-4.11' of git://git.infradead.org/users/willy/linux-dax: radix tree test suite: Specify -m32 in LDFLAGS too ida: Free correct IDA bitmap radix tree test suite: Depend on Makefile and quieten grep radix tree test suite: Fix build with --as-needed radix tree test suite: Build 32 bit binaries radix tree test suite: Add performance test for radix_tree_join() radix tree test suite: Add performance test for radix_tree_split() radix tree test suite: Add performance benchmarks radix tree test suite: Add test for radix_tree_clear_tags() radix tree test suite: Add tests for ida_simple_get() and ida_simple_remove() radix tree test suite: Add test for idr_get_next()
| * | | | radix tree test suite: Specify -m32 in LDFLAGS tooMatthew Wilcox2017-03-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Michael's patch to use the default make rule for linking and the patch from Rehas to use -m32 if building a 32-bit test-suite on a 64-bit platform don't work well together. Reported-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | ida: Free correct IDA bitmapMatthew Wilcox2017-03-073-3/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's a relatively rare race where we look at the per-cpu preallocated IDA bitmap, see it's NULL, allocate a new one, and atomically update it. If the kmalloc() happened to sleep and we were rescheduled to a different CPU, or an interrupt came in at the exact right time, another task might have successfully allocated a bitmap and already deposited it. I forgot what the semantics of cmpxchg() were and ended up freeing the wrong bitmap leading to KASAN reporting a use-after-free. Dmitry found the bug with syzkaller & wrote the patch. I wrote the test case that will reproduce the bug without his patch being applied. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Depend on Makefile and quieten grepMatthew Wilcox2017-03-071-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Changing the CFLAGS in the Makefile didn't always lead to a recompilation because the OFILES didn't depend on the Makefile. Also, after doing make clean, grep would still complain about a missing map-shift.h; we need -s as well as -q. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Fix build with --as-neededMichael Ellerman2017-03-071-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the radix tree test suite doesn't build with toolchains that use --as-needed by default, for example Ubuntu's: cc -I. -I../../include -g -O2 -Wall -D_LGPL_SOURCE -fsanitize=address -lpthread -lurcu main.o ... -o main /usr/bin/ld: regression1.o: undefined reference to symbol 'pthread_join@@GLIBC_2.17' /lib/powerpc64le-linux-gnu/libpthread.so.0: error adding symbols: DSO missing from command line collect2: error: ld returned 1 exit status This is caused by the custom makefile rules placing LDFLAGS before the .o files that need the libraries. We could fix it by using --no-as-needed, or rewriting the custom rules. But we can also just drop the custom rules and move the libraries to LDLIBS, and then the default rules work correctly - with the one caveat that we need to add -fsanitize=address to LDFLAGS because that must be passed to the linker as well as the compiler. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Build 32 bit binariesRehas Sachdeva2017-03-071-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add option 'make BUILD=32' for building 32-bit binaries. Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Add performance test for radix_tree_join()Rehas Sachdeva2017-03-071-0/+47
| | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Add performance test for radix_tree_split()Rehas Sachdeva2017-03-071-0/+44
| | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Add performance benchmarksRehas Sachdeva2017-03-071-7/+75
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add performance benchmarks for radix tree insertion, tagging and deletion. Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Add test for radix_tree_clear_tags()Rehas Sachdeva2017-03-071-0/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Assert that radix_tree_clear_tags() clears the tags on the passed node and slot. Assert that the case where the radix tree has only one entry at index zero and the node is NULL, is also handled. Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Add tests for ida_simple_get() and ida_simple_remove()Rehas Sachdeva2017-03-071-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Assert that ida_simple_get() allocates an id in the passed range or returns error on failure, and ida_simple_remove() releases an allocated id. Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | radix tree test suite: Add test for idr_get_next()Rehas Sachdeva2017-03-071-0/+25
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | Assert that idr_get_next() returns the next populated entry in the tree with an ID greater than or equal to the value pointed to by @nextid argument. Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
* | | | Merge tag 'powerpc-4.11-3' of ↵Linus Torvalds2017-03-071-2/+4
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "Five fairly small fixes for things that went in this cycle. A fairly large patch to rework the CAS logic on Power9, necessitated by a late change to the firmware API, and we can't boot without it. Three fixes going to stable, allowing more instructions to be emulated on LE, fixing a boot crash on 32-bit Freescale BookE machines, and the OPAL XICS workaround. And a patch from me to sort the selects under CONFIG PPC. Annoying churn, but worth it in the long run, and best for it to go in now to avoid conflicts. Thanks to: Alexey Kardashevskiy, Anton Blanchard, Balbir Singh, Gautham R. Shenoy, Laurentiu Tudor, Nicholas Piggin, Paul Mackerras, Ravi Bangoria, Sachin Sant, Shile Zhang, Suraj Jitindar Singh" * tag 'powerpc-4.11-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc: Sort the selects under CONFIG_PPC powerpc/64: Fix L1D cache shape vector reporting L1I values powerpc/64: Avoid panic during boot due to divide by zero in init_cache_info() powerpc: Update to new option-vector-5 format for CAS powerpc: Parse the command line before calling CAS powerpc/xics: Work around limitations of OPAL XICS priority handling powerpc/64: Fix checksum folding in csum_add() powerpc/powernv: Fix opal tracepoints with JUMP_LABEL=n powerpc/booke: Fix boot crash due to null hugepd powerpc: Fix compiling a BE kernel with a powerpc64le toolchain selftest/powerpc: Fix false failures for skipped tests powerpc/powernv: Fix bug due to labeling ambiguity in power_enter_stop powerpc/64: Invalidate process table caching after setting process table powerpc: emulate_step() tests for load/store instructions powerpc: Emulation support for load/store instructions on LE
| * | | selftest/powerpc: Fix false failures for skipped testsSachin Sant2017-03-031-2/+4
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Tests under alignment subdirectory are skipped when executed on previous generation hardware, but harness still marks them as failed. test: test_copy_unaligned tags: git_version:unknown [SKIP] Test skipped on line 26 skip: test_copy_unaligned selftests: copy_unaligned [FAIL] The MAGIC_SKIP_RETURN_VALUE value assigned to rc variable is retained till the program exit which causes the test to be marked as failed. This patch resets the value before returning to the main() routine. With this patch the test o/p is as follows: test: test_copy_unaligned tags: git_version:unknown [SKIP] Test skipped on line 26 skip: test_copy_unaligned selftests: copy_unaligned [PASS] Signed-off-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | | Merge tag 'kvm-4.11-2' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2017-03-042-1/+171
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more KVM updates from Radim Krčmář: "Second batch of KVM changes for the 4.11 merge window: PPC: - correct assumption about ASDR on POWER9 - fix MMIO emulation on POWER9 x86: - add a simple test for ioperm - cleanup TSS (going through KVM tree as the whole undertaking was caused by VMX's use of TSS) - fix nVMX interrupt delivery - fix some performance counters in the guest ... and two cleanup patches" * tag 'kvm-4.11-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: nVMX: Fix pending events injection x86/kvm/vmx: remove unused variable in segment_base() selftests/x86: Add a basic selftest for ioperm x86/asm: Tidy up TSS limit code kvm: convert kvm.users_count from atomic_t to refcount_t KVM: x86: never specify a sample period for virtualized in_tx_cp counters KVM: PPC: Book3S HV: Don't use ASDR for real-mode HPT faults on POWER9 KVM: PPC: Book3S HV: Fix software walk of guest process page tables
| * | | selftests/x86: Add a basic selftest for iopermAndy Lutomirski2017-03-012-1/+171
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This doesn't fully exercise the interaction between KVM and ioperm(), but it does test basic functionality. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* | | | Merge branch 'work.misc' of ↵Linus Torvalds2017-03-034-0/+24
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc final vfs updates from Al Viro: "A few unrelated patches that got beating in -next. Everything else will have to go into the next window ;-/" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: hfs: fix hfs_readdir() selftest for default_file_splice_read() infoleak 9p: constify ->d_name handling
| * | | | selftest for default_file_splice_read() infoleakAl Viro2017-02-184-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bug fixed in commit b9dc6f65bc5e ("fix a fencepost error in pipe_advance()") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | | Merge branch 'libnvdimm-fixes' of ↵Linus Torvalds2017-03-031-7/+7
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm fixes from Dan Williams: "A fix and regression test case for nvdimm namespace label compatibility. Details: - An "nvdimm namespace label" is metadata on an nvdimm that provisions dimm capacity into a "namespace" that can host a block device / dax-filesytem, or a device-dax character device. A namespace is an object that other operating environment and platform firmware needs to comprehend for capabilities like booting from an nvdimm. The label metadata contains a checksum that Linux was not calculating correctly leading to other environments rejecting the Linux label. These have received a build success notification from the kbuild robot, and a positive test result from Nick who reported the problem" * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: nfit, libnvdimm: fix interleave set cookie calculation tools/testing/nvdimm: make iset cookie predictable
| * | | | | tools/testing/nvdimm: make iset cookie predictableDan Williams2017-03-011-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For testing changes to the iset cookie algorithm we need a value that is constant from run-to-run. Stop including dynamic data in the emulated region_offset values. Also, pick values that sort in a different order depending on whether the comparison is a memcmp() of two 8-byte arrays or subtraction of two 64-bit values. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | | | | | Merge tag 'linux-kselftest-4.11-rc1-urgent_fix' of ↵Linus Torvalds2017-03-031-0/+4
|\ \ \ \ \ \ | |_|_|_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kselftest fix from Shuah Khan: "This update consists of an urgent fix for individual test build failures introduced in the 4.11-rc1 update" * tag 'linux-kselftest-4.11-rc1-urgent_fix' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: selftests: lib.mk Fix individual test builds
| * | | | | selftests: lib.mk Fix individual test buildsShuah Khan2017-03-021-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit a8ba798bc8ec ("selftests: enable O and KBUILD_OUTPUT"), added support to generate compile targets in a user specified directory. OUTPUT variable controls the location which is undefined when tests are built in the test directory or with "make -C tools/testing/selftests/x86". make -C tools/testing/selftests/x86/ make: Entering directory '/lkml/linux_4.11/tools/testing/selftests/x86' Makefile:44: warning: overriding recipe for target 'clean' ../lib.mk:51: warning: ignoring old recipe for target 'clean' gcc -m64 -o /single_step_syscall_64 -O2 -g -std=gnu99 -pthread -Wall single_step_syscall.c -lrt -ldl /usr/bin/ld: cannot open output file /single_step_syscall_64: Permission denied collect2: error: ld returned 1 exit status Makefile:50: recipe for target '/single_step_syscall_64' failed make: *** [/single_step_syscall_64] Error 1 make: Leaving directory '/lkml/linux_4.11/tools/testing/selftests/x86' Same failure with "cd tools/testing/selftests/x86/;make" run. Fix this with a change to lib.mk to define OUTPUT to be the pwd when MAKELEVEL is 0. This covers both cases mentioned above. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
* | | | | | Merge branch 'idr-4.11' of git://git.infradead.org/users/willy/linux-daxLinus Torvalds2017-02-2835-708/+668
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull IDR rewrite from Matthew Wilcox: "The most significant part of the following is the patch to rewrite the IDR & IDA to be clients of the radix tree. But there's much more, including an enhancement of the IDA to be significantly more space efficient, an IDR & IDA test suite, some improvements to the IDR API (and driver changes to take advantage of those improvements), several improvements to the radix tree test suite and RCU annotations. The IDR & IDA rewrite had a good spin in linux-next and Andrew's tree for most of the last cycle. Coupled with the IDR test suite, I feel pretty confident that any remaining bugs are quite hard to hit. 0-day did a great job of watching my git tree and pointing out problems; as it hit them, I added new test-cases to be sure not to be caught the same way twice" Willy goes on to expand a bit on the IDR rewrite rationale: "The radix tree and the IDR use very similar data structures. Merging the two codebases lets us share the memory allocation pools, and results in a net deletion of 500 lines of code. It also opens up the possibility of exposing more of the features of the radix tree to users of the IDR (and I have some interesting patches along those lines waiting for 4.12) It also shrinks the size of the 'struct idr' from 40 bytes to 24 which will shrink a fair few data structures that embed an IDR" * 'idr-4.11' of git://git.infradead.org/users/willy/linux-dax: (32 commits) radix tree test suite: Add config option for map shift idr: Add missing __rcu annotations radix-tree: Fix __rcu annotations radix-tree: Add rcu_dereference and rcu_assign_pointer calls radix tree test suite: Run iteration tests for longer radix tree test suite: Fix split/join memory leaks radix tree test suite: Fix leaks in regression2.c radix tree test suite: Fix leaky tests radix tree test suite: Enable address sanitizer radix_tree_iter_resume: Fix out of bounds error radix-tree: Store a pointer to the root in each node radix-tree: Chain preallocated nodes through ->parent radix tree test suite: Dial down verbosity with -v radix tree test suite: Introduce kmalloc_verbose idr: Return the deleted entry from idr_remove radix tree test suite: Build separate binaries for some tests ida: Use exceptional entries for small IDAs ida: Move ida_bitmap to a percpu variable Reimplement IDR and IDA using the radix tree radix-tree: Add radix_tree_iter_delete ...
| * | | | | | radix tree test suite: Add config option for map shiftRehas Sachdeva2017-02-134-11/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add config option "SHIFT=<value>" to Makefile for building test suite with any value of RADIX_TREE_MAP_SHIFT between 3 and 7 inclusive. Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> [mawilcox@microsoft.com: .gitignore, quieten grep, remove on clean] Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | | | radix tree test suite: Run iteration tests for longerMatthew Wilcox2017-02-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the -l flag is set, run the tests for 100 seconds each instead of the normal 10 seconds. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>
| * | | | | | radix tree test suite: Fix split/join memory leaksMatthew Wilcox2017-02-131-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The last of the memory leaks in the test suite was a couple of places in the split/join testing where I forgot to free the element being removed from the tree. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>
| * | | | | | radix tree test suite: Fix leaks in regression2.cMatthew Wilcox2017-02-131-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | None of the malloc'ed data structures were ever being freed. Found with -fsanitize=address. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>
| * | | | | | radix tree test suite: Fix leaky testsMatthew Wilcox2017-02-131-12/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If item_insert() or item_insert_order() failed to insert an item, they would leak the item they had just created. This was causing runaway memory consumption while running the iteration_check testcase, which proves that Ross has too much memory in his workstation ;-) Make sure to free the item on error. Found with -fsanitize=address. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>
| * | | | | | radix tree test suite: Enable address sanitizerMatthew Wilcox2017-02-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I was looking for a memory scribble and instead found a pile of memory leaks. Ensure no more occur in future. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>
| * | | | | | radix-tree: Chain preallocated nodes through ->parentMatthew Wilcox2017-02-131-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Chaining through the ->private_data member means we have to zero ->private_data after removing preallocated nodes from the list. We're about to initialise ->parent anyway, so we can avoid zeroing it. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | | | radix tree test suite: Dial down verbosity with -vRehas Sachdeva2017-02-1310-58/+77
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the output of radix tree test suite less verbose by default and add -v and -vv command line options for increasing level of verbosity. Signed-off-by: Rehas Sachdeva <aquannie@gmail.com> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | | | radix tree test suite: Introduce kmalloc_verboseMatthew Wilcox2017-02-132-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To help track down where memory leaks may be, add the ability to turn on/off printing allocations, frees and delayed frees. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | | | radix tree test suite: Build separate binaries for some testsMatthew Wilcox2017-02-134-7/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To allow developers to run a subset of tests, build separate multiorder and idr-test binaries which will run just the tests in those files. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>
| * | | | | | ida: Use exceptional entries for small IDAsMatthew Wilcox2017-02-131-1/+92
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can use the root entry as a bitmap and save allocating a 128 byte bitmap for an IDA that contains only a few entries (30 on a 32-bit machine, 62 on a 64-bit machine). This costs about 300 bytes of kernel text on x86-64, so as long as 3 IDAs fall into this category, this is a net win for memory consumption. Thanks to Rasmus Villemoes for his work documenting the problem and collecting statistics on IDAs. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | | | ida: Move ida_bitmap to a percpu variableMatthew Wilcox2017-02-132-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we preload the IDA, we allocate an IDA bitmap. Instead of storing that preallocated bitmap in the IDA, we store it in a percpu variable. Generally there are more IDAs in the system than CPUs, so this cuts down on the number of preallocated bitmaps that are unused, and about half of the IDA users did not call ida_destroy() so they were leaking IDA bitmaps. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
| * | | | | | Reimplement IDR and IDA using the radix treeMatthew Wilcox2017-02-138-6/+365
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The IDR is very similar to the radix tree. It has some functionality that the radix tree did not have (alloc next free, cyclic allocation, a callback-based for_each, destroy tree), which is readily implementable on top of the radix tree. A few small changes were needed in order to use a tag to represent nodes with free space below them. More extensive changes were needed to support storing NULL as a valid entry in an IDR. Plain radix trees still interpret NULL as a not-present entry. The IDA is reimplemented as a client of the newly enhanced radix tree. As in the current implementation, it uses a bitmap at the last level of the tree. Signed-off-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * | | | | | radix tree test suite: Remove obsolete CONFIGMatthew Wilcox2017-02-131-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | radix-tree.c doesn't use these CONFIG options any more. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>
| * | | | | | radix tree test suite: Use vpath to find lib filesMatthew Wilcox2017-02-131-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of specifying how to build find_bit.o from lib/find_bit.o, use vpath to tell make where to find find_bit.c. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>