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2017-11-02x86/entry/32: Fix cpu_current_top_of_stack initialization at bootAndy Lutomirski1-2/+1
cpu_current_top_of_stack's initialization forgot about TOP_OF_KERNEL_STACK_PADDING. This bug didn't matter because the idle threads never enter user mode. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/e5e370a7e6e4fddd1c4e4cf619765d96bb874b21.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Remove all remaining direct thread_struct::sp0 readsAndy Lutomirski4-4/+10
The only remaining readers in context switch code or vm86(), and they all just want to update TSS.sp0 to match the current task. Replace them all with a new helper update_sp0(). Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2d231687f4ff288c9d9e98d7861b7df374246ac3.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Stop initializing TSS.sp0 at bootAndy Lutomirski2-4/+17
In my quest to get rid of thread_struct::sp0, I want to clean up or remove all of its readers. Two of them are in cpu_init() (32-bit and 64-bit), and they aren't needed. This is because we never enter userspace at all on the threads that CPUs are initialized in. Poison the initial TSS.sp0 and stop initializing it on CPU init. The comment text mostly comes from Dave Hansen. Thanks! Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/ee4a00540ad28c6cff475fbcc7769a4460acc861.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/xen/64, x86/entry/64: Clean up SP code in cpu_initialize_context()Andy Lutomirski1-3/+14
I'm removing thread_struct::sp0, and Xen's usage of it is slightly dubious and unnecessary. Use appropriate helpers instead. While we're at at, reorder the code slightly to make it more obvious what's going on. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/d5b9a3da2b47c68325bd2bbe8f82d9554dee0d0f.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry: Add task_top_of_stack() to find the top of a task's stackAndy Lutomirski1-0/+2
This will let us get rid of a few places that hardcode accesses to thread.sp0. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/b49b3f95a8ff858c40c9b0f5b32be0355324327d.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Pass SP0 directly to load_sp0()Andy Lutomirski8-25/+20
load_sp0() had an odd signature: void load_sp0(struct tss_struct *tss, struct thread_struct *thread); Simplify it to: void load_sp0(unsigned long sp0); Also simplify a few get_cpu()/put_cpu() sequences to preempt_disable()/preempt_enable(). Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2655d8b42ed940aa384fe18ee1129bbbcf730a08.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/32: Pull the MSR_IA32_SYSENTER_CS update code out of native_load_sp0()Andy Lutomirski5-10/+21
This causes the MSR_IA32_SYSENTER_CS write to move out of the paravirt callback. This shouldn't affect Xen PV: Xen already ignores MSR_IA32_SYSENTER_ESP writes. In any event, Xen doesn't support vm86() in a useful way. Note to any potential backporters: This patch won't break lguest, as lguest didn't have any SYSENTER support at all. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/75cf09fe03ae778532d0ca6c65aa58e66bc2f90c.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: De-Xen-ify our NMI codeAndy Lutomirski1-12/+18
Xen PV is fundamentally incompatible with our fancy NMI code: it doesn't use IST at all, and Xen entries clobber two stack slots below the hardware frame. Drop Xen PV support from our NMI code entirely. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/bfbe711b5ae03f672f8848999a8eb2711efc7f98.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02xen, x86/entry/64: Add xen NMI trap entryJuergen Gross4-4/+4
Instead of trying to execute any NMI via the bare metal's NMI trap handler use a Xen specific one for PV domains, like we do for e.g. debug traps. As in a PV domain the NMI is handled via the normal kernel stack this is the correct thing to do. This will enable us to get rid of the very fragile and questionable dependencies between the bare metal NMI handler and Xen assumptions believed to be broken anyway. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/5baf5c0528d58402441550c5770b98e7961e7680.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Remove the RESTORE_..._REGS infrastructureAndy Lutomirski1-52/+0
All users of RESTORE_EXTRA_REGS, RESTORE_C_REGS and such, and REMOVE_PT_GPREGS_FROM_STACK are gone. Delete the macros. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/c32672f6e47c561893316d48e06c7656b1039a36.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Use POP instead of MOV to restore regs on NMI returnAndy Lutomirski1-4/+7
This gets rid of the last user of the old RESTORE_..._REGS infrastructure. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/652a260f17a160789bc6a41d997f98249b73e2ab.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Merge the fast and slow SYSRET pathsAndy Lutomirski1-3/+3
They did almost the same thing. Remove a bunch of pointless instructions (mostly hidden in macros) and reduce cognitive load by merging them. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1204e20233fcab9130a1ba80b3b1879b5db3fc1f.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Use pop instead of movq in syscall_return_via_sysretAndy Lutomirski1-3/+11
Saves 64 bytes. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/6609b7f74ab31c36604ad746e019ea8495aec76c.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Shrink paranoid_exit_restore and make labels localAndy Lutomirski1-8/+5
paranoid_exit_restore was a copy of restore_regs_and_return_to_kernel. Merge them and make the paranoid_exit internal labels local. Keeping .Lparanoid_exit makes the code a bit shorter because it allows a 2-byte jnz instead of a 5-byte jnz. Saves 96 bytes of text. ( This is still a bit suboptimal in a non-CONFIG_TRACE_IRQFLAGS kernel, but fixing that would make the code rather messy. ) Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/510d66a1895cda9473c84b1086f0bb974f22de6a.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Simplify reg restore code in the standard IRET pathsAndy Lutomirski2-6/+27
The old code restored all the registers with movq instead of pop. In theory, this was done because some CPUs have higher movq throughput, but any gain there would be tiny and is almost certainly outweighed by the higher text size. This saves 96 bytes of text. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/ad82520a207ccd851b04ba613f4f752b33ac05f7.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Move SWAPGS into the common IRET-to-usermode pathAndy Lutomirski2-20/+15
All of the code paths that ended up doing IRET to usermode did SWAPGS immediately beforehand. Move the SWAPGS into the common code. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/27fd6f45b7cd640de38fb9066fd0349bcd11f8e1.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Split the IRET-to-user and IRET-to-kernel pathsAndy Lutomirski3-11/+27
These code paths will diverge soon. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/dccf8c7b3750199b4b30383c812d4e2931811509.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Remove the restore_c_regs_and_iret labelAndy Lutomirski1-3/+2
The only user was the 64-bit opportunistic SYSRET failure path, and that path didn't really need it. This change makes the opportunistic SYSRET code a bit more straightforward and gets rid of the label. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/be3006a7ad3326e3458cf1cc55d416252cbe1986.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02Merge branch 'x86/fpu' into x86/asmIngo Molnar9-44/+208
We are about to commit complex rework of various x86 entry code details - create a unified base tree (with FPU commits included) before doing that. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02KEYS: fix out-of-bounds read during ASN.1 parsingEric Biggers1-0/+3
syzkaller with KASAN reported an out-of-bounds read in asn1_ber_decoder(). It can be reproduced by the following command, assuming CONFIG_X509_CERTIFICATE_PARSER=y and CONFIG_KASAN=y: keyctl add asymmetric desc $'\x30\x30' @s The bug is that the length of an ASN.1 data value isn't validated in the case where it is encoded using the short form, causing the decoder to read past the end of the input buffer. Fix it by validating the length. The bug report was: BUG: KASAN: slab-out-of-bounds in asn1_ber_decoder+0x10cb/0x1730 lib/asn1_decoder.c:233 Read of size 1 at addr ffff88003cccfa02 by task syz-executor0/6818 CPU: 1 PID: 6818 Comm: syz-executor0 Not tainted 4.14.0-rc7-00008-g5f479447d983 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0xb3/0x10b lib/dump_stack.c:52 print_address_description+0x79/0x2a0 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x236/0x340 mm/kasan/report.c:409 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427 asn1_ber_decoder+0x10cb/0x1730 lib/asn1_decoder.c:233 x509_cert_parse+0x1db/0x650 crypto/asymmetric_keys/x509_cert_parser.c:89 x509_key_preparse+0x64/0x7a0 crypto/asymmetric_keys/x509_public_key.c:174 asymmetric_key_preparse+0xcb/0x1a0 crypto/asymmetric_keys/asymmetric_type.c:388 key_create_or_update+0x347/0xb20 security/keys/key.c:855 SYSC_add_key security/keys/keyctl.c:122 [inline] SyS_add_key+0x1cd/0x340 security/keys/keyctl.c:62 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x447c89 RSP: 002b:00007fca7a5d3bd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8 RAX: ffffffffffffffda RBX: 00007fca7a5d46cc RCX: 0000000000447c89 RDX: 0000000020006f4a RSI: 0000000020006000 RDI: 0000000020001ff5 RBP: 0000000000000046 R08: fffffffffffffffd R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fca7a5d49c0 R15: 00007fca7a5d4700 Fixes: 42d5ec27f873 ("X.509: Add an ASN.1 decoder") Cc: <stable@vger.kernel.org> # v3.7+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-11-02KEYS: trusted: fix writing past end of buffer in trusted_read()Eric Biggers1-11/+12
When calling keyctl_read() on a key of type "trusted", if the user-supplied buffer was too small, the kernel ignored the buffer length and just wrote past the end of the buffer, potentially corrupting userspace memory. Fix it by instead returning the size required, as per the documentation for keyctl_read(). We also don't even fill the buffer at all in this case, as this is slightly easier to implement than doing a short read, and either behavior appears to be permitted. It also makes it match the behavior of the "encrypted" key type. Fixes: d00a1c72f7f4 ("keys: add new trusted key-type") Reported-by: Ben Hutchings <ben@decadent.org.uk> Cc: <stable@vger.kernel.org> # v2.6.38+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-11-02KEYS: return full count in keyring_read() if buffer is too smallEric Biggers1-20/+19
Commit e645016abc80 ("KEYS: fix writing past end of user-supplied buffer in keyring_read()") made keyring_read() stop corrupting userspace memory when the user-supplied buffer is too small. However it also made the return value in that case be the short buffer size rather than the size required, yet keyctl_read() is actually documented to return the size required. Therefore, switch it over to the documented behavior. Note that for now we continue to have it fill the short buffer, since it did that before (pre-v3.13) and dump_key_tree_aux() in keyutils arguably relies on it. Fixes: e645016abc80 ("KEYS: fix writing past end of user-supplied buffer in keyring_read()") Reported-by: Ben Hutchings <ben@decadent.org.uk> Cc: <stable@vger.kernel.org> # v3.13+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-11-02Merge branch 'x86/mpx/prep' into x86/asmIngo Molnar497-3337/+5444
Pick up some of the MPX commits that modify the syscall entry code, to have a common base and to reduce conflicts. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02ALSA: usb-audio: support new Amanero Combo384 firmware versionJussi Laako1-0/+1
Support DSD_U32_BE sample format on new Amanero Combo384 firmware version on older VID/PID. Fixes: 3eff682d765b ("ALSA: usb-audio: Support both DSD LE/BE Amanero firmware versions") Signed-off-by: Jussi Laako <jussi@sonarnerd.net> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-11-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller2-1/+2
Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains two one-liner fixes for your net tree, they are: 1) Disable fast hash operations for 2-bytes length keys which is leading to incorrect lookups in nf_tables, from Anatole Denis. 2) Reload pointer ipv4 header after ip_route_me_harder() given this may result in use-after-free due to skbuff header reallocation, patch from Tejaswi Tanikella. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02net: vrf: correct FRA_L3MDEV encode typeJeff Barnhill1-1/+1
FRA_L3MDEV is defined as U8, but is being added as a U32 attribute. On big endian architecture, this results in the l3mdev entry not being added to the FIB rules. Fixes: 1aa6c4f6b8cd8 ("net: vrf: Add l3mdev rules on first device create") Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02tcp_nv: fix division by zero in tcpnv_acked()Konstantin Khlebnikov1-1/+1
Average RTT could become zero. This happened in real life at least twice. This patch treats zero as 1us. Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by: Lawrence Brakmo <Brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02Merge branch 'drm-fixes-4.14' of git://people.freedesktop.org/~agd5f/linux ↵Dave Airlie2-6/+10
into drm-fixes Just two small patches for stable to fix the driver failing to load on polaris cards with harvested VCE or UVD blocks. * 'drm-fixes-4.14' of git://people.freedesktop.org/~agd5f/linux: drm/amdgpu: allow harvesting check for Polaris VCE drm/amdgpu: return -ENOENT from uvd 6.0 early init for harvesting
2017-11-02drm/amdgpu: allow harvesting check for Polaris VCELeo Liu1-6/+6
Fixes init failures on Polaris cards with harvested VCE blocks. Signed-off-by: Leo Liu <leo.liu@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org
2017-11-02drm/amdgpu: return -ENOENT from uvd 6.0 early init for harvestingLeo Liu1-0/+4
Fixes init failures on polaris cards with harvested UVD. Signed-off-by: Leo Liu <leo.liu@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org
2017-11-02Merge tag 'drm-intel-fixes-2017-11-01' of ↵Dave Airlie7-35/+57
git://anongit.freedesktop.org/drm/drm-intel into drm-fixes Fixes for Stable: - Fix KBL Blank Screen (Jani) - Fix FIFO Underrun on SNB (Maarten) Other fixes: - Fix GPU Hang on i915gm (Chris) - Fix gem_tiled_pread_pwrite IGT case (Chris) - Cancel modeset retry work during modeset clean-up (Manasi) * tag 'drm-intel-fixes-2017-11-01' of git://anongit.freedesktop.org/drm/drm-intel: drm/i915: Check incoming alignment for unfenced buffers (on i915gm) drm/i915: Hold rcu_read_lock when iterating over the radixtree (vma idr) drm/i915: Hold rcu_read_lock when iterating over the radixtree (objects) drm/i915/edp: read edp display control registers unconditionally drm/i915: Do not rely on wm preservation for ILK watermarks drm/i915: Cancel the modeset retry work during modeset cleanup
2017-11-02ARM: add debug ".edata_real" symbolRussell King1-0/+9
Add an additional symbol to the decompressor image, which will allow future debugging of non-bootable problems similar to the one encountered with the EFI stub. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-11-02MIPS: smp-cmp: Fix vpe_id build errorJames Hogan1-2/+2
The smp-cmp build has been (further) broken since commit 856fbcee6099 ("MIPS: Store core & VP IDs in GlobalNumber-style variable") in v4.14-rc1 like so: arch/mips/kernel/smp-cmp.c: In function ‘cmp_init_secondary’: arch/mips/kernel/smp-cmp.c:53:4: error: ‘struct cpuinfo_mips’ has no member named ‘vpe_id’ c->vpe_id = (read_c0_tcbind() >> TCBIND_CURVPE_SHIFT) & ^ Fix by replacing vpe_id with cpu_set_vpe_id(). Fixes: 856fbcee6099 ("MIPS: Store core & VP IDs in GlobalNumber-style variable") Signed-off-by: James Hogan <jhogan@kernel.org> Reviewed-by: Paul Burton <paul.burton@imgtec.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17569/ Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-02Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull signal bugfix from Eric Biederman: "When making the generic support for SIGEMT conditional on the presence of SIGEMT I made a typo that causes it to fail to activate. It was noticed comparatively quickly but the bug report just made it to me today" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: signal: Fix name of SIGEMT in #if defined() check
2017-11-02MAINTAINERS: Update Pistachio platform maintainersJames Hartley1-3/+2
Neither of the current maintainers works for Imagination any more. Removed both imgtec email addresses and added back mine for occasional reviews, also changed from Maintained to Odd Fixes to reflect the time that I will be able to spend on it. Signed-off-by: James Hartley <james.hartley@sondrel.com> Patchwork: https://patchwork.linux-mips.org/patch/17475/ Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-02MIPS: smp-cmp: Use right include for task_structJason A. Donenfeld1-1/+1
When task_struct was moved, this MIPS code was neglected. Evidently nobody is using it anymore. This fixes this build error: In file included from ./arch/mips/include/asm/thread_info.h:15:0, from ./include/linux/thread_info.h:37, from ./include/asm-generic/current.h:4, from ./arch/mips/include/generated/asm/current.h:1, from ./include/linux/sched.h:11, from arch/mips/kernel/smp-cmp.c:22: arch/mips/kernel/smp-cmp.c: In function ‘cmp_boot_secondary’: ./arch/mips/include/asm/processor.h:384:41: error: implicit declaration of function ‘task_stack_page’ [-Werror=implicit-function-declaration] #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \ ^ arch/mips/kernel/smp-cmp.c:84:21: note: in expansion of macro ‘__KSTK_TOS’ unsigned long sp = __KSTK_TOS(idle); ^~~~~~~~~~ Fixes: f3ac60671954 ("sched/headers: Move task-stack related APIs from <linux/sched.h> to <linux/sched/task_stack.h>") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: <stable@vger.kernel.org> # 4.11+ Patchwork: https://patchwork.linux-mips.org/patch/17522/ Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-02signal: Fix name of SIGEMT in #if defined() checkAndrew Clayton1-1/+1
Commit cc731525f26a ("signal: Remove kernel interal si_code magic") added a check for SIGMET and NSIGEMT being defined. That SIGMET should in fact be SIGEMT, with SIGEMT being defined in arch/{alpha,mips,sparc}/include/uapi/asm/signal.h This was actually pointed out by BenHutchings in a lwn.net comment here https://lwn.net/Comments/734608/ Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic") Signed-off-by: Andrew Clayton <andrew@digital-domain.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-11-02Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds4-4/+21
Pull block fixes from Jens Axboe: "A few fixes that should go into this series: - Regression fix for ide-cd, ensuring that a request is fully initialized. From Hongxu. - Ditto fix for virtio_blk, from Bart. - NVMe fix from Keith, ensuring that we set the right block size on revalidation. If the block size changed, we'd be in trouble without it. - NVMe rdma fix from Sagi, fixing a potential hang while the controller is being removed" * 'for-linus' of git://git.kernel.dk/linux-block: ide:ide-cd: fix kernel panic resulting from missing scsi_req_init nvme: Fix setting logical block format when revalidating virtio_blk: Fix an SG_IO regression nvme-rdma: fix possible hang when issuing commands during ctrl removal
2017-11-02MIPS: Update Goldfish RTC driver maintainer email addressAleksandar Markovic2-1/+2
Change all relevant instances of miodrag.dinic@imgtec.com email address to miodrag.dinic@mips.com. Signed-off-by: Miodrag Dinic <miodrag.dinic@mips.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/17515/ [jhogan@kernel.org: Fix .mailmap direction] Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-02MIPS: Update RINT emulation maintainer email addressAleksandar Markovic2-1/+2
Change all relevant instances of aleksandar.markovic@imgtec.com email address to aleksandar.markovic@mips.com. Signed-off-by: Miodrag Dinic <miodrag.dinic@mips.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Patchwork: https://patchwork.linux-mips.org/patch/17514/ Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-02MIPS: CPS: Fix use of current_cpu_data in preemptible codeMatt Redfearn1-1/+1
Commit 1ec9dd80bedc ("MIPS: CPS: Detect CPUs in secondary clusters") added a check in cps_boot_secondary() that the secondary being booted is in the same cluster as the CPU running this code. This check is performed using current_cpu_data without disabling preemption. As such when CONFIG_PREEMPT=y, a BUG is triggered: [ 57.991693] BUG: using smp_processor_id() in preemptible [00000000] code: hotplug/1749 <snip> [ 58.063077] Call Trace: [ 58.065842] [<8040cdb4>] show_stack+0x84/0x114 [ 58.070830] [<80b11b38>] dump_stack+0xf8/0x140 [ 58.075796] [<8079b12c>] check_preemption_disabled+0xec/0x118 [ 58.082204] [<80415110>] cps_boot_secondary+0x84/0x44c [ 58.087935] [<80413a14>] __cpu_up+0x34/0x98 [ 58.092624] [<80434240>] bringup_cpu+0x38/0x114 [ 58.097680] [<80434af0>] cpuhp_invoke_callback+0x168/0x8f0 [ 58.103801] [<804362d0>] _cpu_up+0x154/0x1c8 [ 58.108565] [<804363dc>] do_cpu_up+0x98/0xa8 [ 58.113333] [<808261f8>] device_online+0x84/0xc0 [ 58.118481] [<80826294>] online_store+0x60/0x98 [ 58.123562] [<8062261c>] kernfs_fop_write+0x158/0x1d4 [ 58.129196] [<805a2ae4>] __vfs_write+0x4c/0x168 [ 58.134247] [<805a2dc8>] vfs_write+0xe0/0x190 [ 58.139095] [<805a2fe0>] SyS_write+0x68/0xc4 [ 58.143854] [<80415d58>] syscall_common+0x34/0x58 In reality we don't currently support running the kernel on CPUs not in cluster 0, so the answer to cpu_cluster(&current_cpu_data) will always be 0, even if this task being preempted and continues running on a different CPU. Regardless, the BUG should not be triggered, so fix this by switching to raw_current_cpu_data. When multicluster support lands upstream this check will need removing or changing anyway. Fixes: 1ec9dd80bedc ("MIPS: CPS: Detect CPUs in secondary clusters") Signed-off-by: Matt Redfearn <matt.redfearn@mips.com> Reviewed-by: Paul Burton <paul.burton@mips.com> CC: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17563/ Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-01ptrace,x86: Make user_64bit_mode() available to 32-bit buildsRicardo Neri1-1/+5
In its current form, user_64bit_mode() can only be used when CONFIG_X86_64 is selected. This implies that code built with CONFIG_X86_64=n cannot use it. If a piece of code needs to be built for both CONFIG_X86_64=y and CONFIG_X86_64=n and wants to use this function, it needs to wrap it in an #ifdef/#endif; potentially, in multiple places. This can be easily avoided with a single #ifdef/#endif pair within user_64bit_mode() itself. Suggested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: ricardo.neri@intel.com Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Huang Rui <ray.huang@amd.com> Cc: Qiaowei Ren <qiaowei.ren@intel.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Colin Ian King <colin.king@canonical.com> Cc: Chen Yucong <slaoub@gmail.com> Cc: Adam Buchbinder <adam.buchbinder@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Garnier <thgarnie@google.com> Link: https://lkml.kernel.org/r/1509135945-13762-4-git-send-email-ricardo.neri-calderon@linux.intel.com
2017-11-01x86/boot: Relocate definition of the initial state of CR0Ricardo Neri3-6/+3
Both head_32.S and head_64.S utilize the same value to initialize the control register CR0. Also, other parts of the kernel might want to access this initial definition (e.g., emulation code for User-Mode Instruction Prevention uses this state to provide a sane dummy value for CR0 when emulating the smsw instruction). Thus, relocate this definition to a header file from which it can be conveniently accessed. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: ricardo.neri@intel.com Cc: linux-mm@kvack.org Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Huang Rui <ray.huang@amd.com> Cc: Shuah Khan <shuah@kernel.org> Cc: linux-arch@vger.kernel.org Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jiri Slaby <jslaby@suse.cz> Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Chen Yucong <slaoub@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/1509135945-13762-3-git-send-email-ricardo.neri-calderon@linux.intel.com
2017-11-01x86/mm: Relocate page fault error codes to traps.hRicardo Neri2-54/+52
Up to this point, only fault.c used the definitions of the page fault error codes. Thus, it made sense to keep them within such file. Other portions of code might be interested in those definitions too. For instance, the User- Mode Instruction Prevention emulation code will use such definitions to emulate a page fault when it is unable to successfully copy the results of the emulated instructions to user space. While relocating the error code enumeration, the prefix X86_ is used to make it consistent with the rest of the definitions in traps.h. Of course, code using the enumeration had to be updated as well. No functional changes were performed. Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: ricardo.neri@intel.com Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Huang Rui <ray.huang@amd.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jiri Slaby <jslaby@suse.cz> Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Chen Yucong <slaoub@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: https://lkml.kernel.org/r/1509135945-13762-2-git-send-email-ricardo.neri-calderon@linux.intel.com
2017-11-01x86/mcelog: Get rid of RCU remnantsBorislav Petkov1-94/+27
Jeremy reported a suspicious RCU usage warning in mcelog. /dev/mcelog is called in process context now as part of the notifier chain and doesn't need any of the fancy RCU and lockless accesses which it did in atomic context. Axe it all in favor of a simple mutex synchronization which cures the problem reported. Fixes: 5de97c9f6d85 ("x86/mce: Factor out and deprecate the /dev/mcelog driver") Reported-by: Jeremy Cline <jcline@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-and-tested-by: Tony Luck <tony.luck@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: linux-edac@vger.kernel.org Cc: Laura Abbott <labbott@redhat.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20171101164754.xzzmskl4ngrqc5br@pd.tnic Link: https://bugzilla.redhat.com/show_bug.cgi?id=1498969
2017-11-01watchdog/hardlockup/perf: Use atomics to track in-use cpu counterDon Zickus1-3/+5
Guenter reported: There is still a problem. When running echo 6 > /proc/sys/kernel/watchdog_thresh echo 5 > /proc/sys/kernel/watchdog_thresh repeatedly, the message NMI watchdog: Enabled. Permanently consumes one hw-PMU counter. stops after a while (after ~10-30 iterations, with fluctuations). Maybe watchdog_cpus needs to be atomic ? That's correct as this again is affected by the asynchronous nature of the smpboot thread unpark mechanism. CPU 0 CPU1 CPU2 write(watchdog_thresh, 6) stop() park() update() start() unpark() thread->unpark() cnt++; write(watchdog_thresh, 5) thread->unpark() stop() park() thread->park() cnt--; cnt++; update() start() unpark() That's not a functional problem, it just affects the informational message. Convert watchdog_cpus to atomic_t to prevent the problem Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20171101181126.j727fqjmdthjz4xk@redhat.com
2017-11-01watchdog/harclockup/perf: Revert a33d44843d45 ("watchdog/hardlockup/perf: ↵Thomas Gleixner1-2/+5
Simplify deferred event destroy") Guenter reported a crash in the watchdog/perf code, which is caused by cleanup() and enable() running concurrently. The reason for this is: The watchdog functions are serialized via the watchdog_mutex and cpu hotplug locking, but the enable of the perf based watchdog happens in context of the unpark callback of the smpboot thread. But that unpark function is not synchronous inside the locking. The unparking of the thread just wakes it up and leaves so there is no guarantee when the thread is executing. If it starts running _before_ the cleanup happened then it will create a event and overwrite the dead event pointer. The new event is then cleaned up because the event is marked dead. lock(watchdog_mutex); lockup_detector_reconfigure(); cpus_read_lock(); stop(); park() update(); start(); unpark() cpus_read_unlock(); thread runs() overwrite dead event ptr cleanup(); free new event, which is active inside perf.... unlock(watchdog_mutex); The park side is safe as that actually waits for the thread to reach parked state. Commit a33d44843d45 removed the protection against this kind of scenario under the stupid assumption that the hotplug serialization and the watchdog_mutex cover everything. Bring it back. Reverts: a33d44843d45 ("watchdog/hardlockup/perf: Simplify deferred event destroy") Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Thomas Feels-stupid Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Don Zickus <dzickus@redhat.com> Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1710312145190.1942@nanos
2017-11-01ARM: 8716/1: pass endianness info to sparseLuc Van Oostenryck1-0/+2
ARM depends on the macros '__ARMEL__' & '__ARMEB__' being defined or not to correctly select or define endian-specific macros, structures or pieces of code. These macros are predefined by the compiler but sparse knows nothing about them and thus may pre-process files differently from what gcc would. Fix this by passing '-D__ARMEL__' or '-D__ARMEB__' to sparse, depending on the endianness of the kernel, like defined by GCC. Note: In most case it won't change anything since most ARMs use little-endian (but an allyesconfig would use big-endian!). To: Russell King <linux@armlinux.org.uk> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-11-01drm/vmwgfx: Fix Ubuntu 17.10 Wayland black screen issueSinclair Yeh1-1/+1
This is an extension of Commit 7c20d213dd3c ("drm/vmwgfx: Work around mode set failure in 2D VMs") With Wayland desktop and atomic mode set, during the mode setting process there is a moment when two framebuffer sized surfaces are being pinned. This was not an issue with Xorg. Since this only happens during a mode change, there should be no performance impact by increasing allowable mem_size. Signed-off-by: Sinclair Yeh <syeh@vmware.com> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Cc: stable@vger.kernel.org
2017-11-01drm/vmwgfx: constify vmw_fence_opsArvind Yadav1-1/+1
vmw_fence_ops are not supposed to change at runtime. Functions "dma_fence_init" working with const vmw_fence_ops provided by <linux/dma-fence.h>. So mark the non-const structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>