user/sven/linux.git/arch, branch v4.14.4

Revert "x86/entry/64: Add missing irqflags tracing to native_load_gs_index()"

2017-12-05T10:26:38Z

This reverts commit f9a64e23a9da528e7d8aa1bd2c7bb92be4ebb724 which is commit 0d794d0d018f23fb09c50f6ae26868bd6ae343d6 upstream. Andy writes: I think the thing to do is to revert the patch from -stable. The bug it fixes is very minor, and the regression is that it made a pre-existing bug in some nearly-undebuggable core resume code much easier to hit. I don't feel comfortable with a backport of the latter fix until it has a good long soak in Linus' tree. Reported-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

KVM: lapic: Fixup LDR on load in x2apic

2017-12-05T10:26:32Z

commit 12806ba937382fdfdbad62a399aa2dce65c10fcd upstream. In x2apic mode the LDR is fixed based on the ID rather than separately loadable like it was before x2. When kvm_apic_set_state is called, the base is set, and if it has the X2APIC_ENABLE flag set then the LDR is calculated; however that value gets overwritten by the memcpy a few lines below overwriting it with the value that came from userland. The symptom is a lack of EOI after loading the state (e.g. after a QEMU migration) and is due to the EOI bitmap being wrong due to the incorrect LDR. This was seen with a Win2016 guest under Qemu with irqchip=split whose USB mouse didn't work after a VM migration. This corresponds to RH bug: https://bugzilla.redhat.com/show_bug.cgi?id=1502591 Reported-by: Yiqian Wei Signed-off-by: Dr. David Alan Gilbert [Applied fixup from Liran Alon. - Paolo] Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

KVM: lapic: Split out x2apic ldr calculation

2017-12-05T10:26:32Z

commit e872fa94662d0644057c7c80b3071bdb9249e5ab upstream. Split out the ldr calculation from kvm_apic_set_x2apic_id since we're about to reuse it in the following patch. Signed-off-by: Dr. David Alan Gilbert Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

KVM: x86: inject exceptions produced by x86_decode_insn

2017-12-05T10:26:32Z

commit 6ea6e84309ca7e0e850b3083e6b09344ee15c290 upstream. Sometimes, a processor might execute an instruction while another processor is updating the page tables for that instruction's code page, but before the TLB shootdown completes. The interesting case happens if the page is in the TLB. In general, the processor will succeed in executing the instruction and nothing bad happens. However, what if the instruction is an MMIO access? If *that* happens, KVM invokes the emulator, and the emulator gets the updated page tables. If the update side had marked the code page as non present, the page table walk then will fail and so will x86_decode_insn. Unfortunately, even though kvm_fetch_guest_virt is correctly returning X86EMUL_PROPAGATE_FAULT, x86_decode_insn's caller treats the failure as a fatal error if the instruction cannot simply be reexecuted (as is the case for MMIO). And this in fact happened sometimes when rebooting Windows 2012r2 guests. Just checking ctxt->have_exception and injecting the exception if true is enough to fix the case. Thanks to Eduardo Habkost for helping in the debugging of this issue. Reported-by: Yanan Fu Cc: Eduardo Habkost Signed-off-by: Paolo Bonzini Signed-off-by: Radim Krčmář Signed-off-by: Greg Kroah-Hartman

KVM: x86: Exit to user-mode on #UD intercept when emulator requires

2017-12-05T10:26:32Z

commit 61cb57c9ed631c95b54f8e9090c89d18b3695b3c upstream. Instruction emulation after trapping a #UD exception can result in an MMIO access, for example when emulating a MOVBE on a processor that doesn't support the instruction. In this case, the #UD vmexit handler must exit to user mode, but there wasn't any code to do so. Add it for both VMX and SVM. Signed-off-by: Liran Alon Reviewed-by: Nikita Leshenko Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: Konrad Rzeszutek Wilk Reviewed-by: Wanpeng Li Reviewed-by: Paolo Bonzini Signed-off-by: Radim Krčmář Signed-off-by: Greg Kroah-Hartman

KVM: x86: pvclock: Handle first-time write to pvclock-page contains random junk

2017-12-05T10:26:31Z

commit 51c4b8bba674cfd2260d173602c4dac08e4c3a99 upstream. When guest passes KVM it's pvclock-page GPA via WRMSR to MSR_KVM_SYSTEM_TIME / MSR_KVM_SYSTEM_TIME_NEW, KVM don't initialize pvclock-page to some start-values. It just requests a clock-update which will happen before entering to guest. The clock-update logic will call kvm_setup_pvclock_page() to update the pvclock-page with info. However, kvm_setup_pvclock_page() *wrongly* assumes that the version-field is initialized to an even number. This is wrong because at first-time write, field could be any-value. Fix simply makes sure that if first-time version-field is odd, increment it once more to make it even and only then start standard logic. This follows same logic as done in other pvclock shared-pages (See kvm_write_wall_clock() and record_steal_time()). Signed-off-by: Liran Alon Reviewed-by: Nikita Leshenko Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: Konrad Rzeszutek Wilk Reviewed-by: Paolo Bonzini Signed-off-by: Radim Krčmář Signed-off-by: Greg Kroah-Hartman

powerpc/kexec: Fix kexec/kdump in P9 guest kernels

2017-12-05T10:26:31Z

commit 2621e945fbf1d6df5f3f0ba7be5bae3d2cf9b6a5 upstream. The code that cleans up the IAMR/AMOR before kexec'ing failed to remember that when we're running as a guest AMOR is not writable, it's hypervisor privileged. They symptom is that the kexec stops before entering purgatory and nothing else is seen on the console. If you examine the state of the system all threads will be in the 0x700 program check handler. Fix it by making the write to AMOR dependent on HV mode. Fixes: 1e2a516e89fc ("powerpc/kexec: Fix radix to hash kexec due to IAMR/AMOR") Reported-by: Yilin Zhang Debugged-by: David Gibson Signed-off-by: Michael Ellerman Acked-by: Balbir Singh Reviewed-by: David Gibson Tested-by: David Gibson Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

powerpc/powernv: Fix kexec crashes caused by tlbie tracing

2017-12-05T10:26:31Z

commit a3961f824cdbe7eb431254dc7d8f6f6767f474aa upstream. Rebooting into a new kernel with kexec fails in trace_tlbie() which is called from native_hpte_clear(). This happens if the running kernel has CONFIG_LOCKDEP enabled. With lockdep enabled, the tracepoints always execute few RCU checks regardless of whether tracing is on or off. We are already in the last phase of kexec sequence in real mode with HILE_BE set. At this point the RCU check ends up in RCU_LOCKDEP_WARN and causes kexec to fail. Fix this by not calling trace_tlbie() from native_hpte_clear(). mpe: It's not safe to call trace points at this point in the kexec path, even if we could avoid the RCU checks/warnings. The only solution is to not call them. Fixes: 0428491cba92 ("powerpc/mm: Trace tlbie(l) instructions") Signed-off-by: Mahesh Salgaonkar Reported-by: Aneesh Kumar K.V Suggested-by: Michael Ellerman Acked-by: Naveen N. Rao Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

arm64: ftrace: emit ftrace-mod.o contents through code

2017-12-05T10:26:31Z

commit be0f272bfc83797f70d44faca86954df62e2bbc0 upstream. When building the arm64 kernel with both CONFIG_ARM64_MODULE_PLTS and CONFIG_DYNAMIC_FTRACE enabled, the ftrace-mod.o object file is built with the kernel and contains a trampoline that is linked into each module, so that modules can be loaded far away from the kernel and still reach the ftrace entry point in the core kernel with an ordinary relative branch, as is emitted by the compiler instrumentation code dynamic ftrace relies on. In order to be able to build out of tree modules, this object file needs to be included into the linux-headers or linux-devel packages, which is undesirable, as it makes arm64 a special case (although a precedent does exist for 32-bit PPC). Given that the trampoline essentially consists of a PLT entry, let's not bother with a source or object file for it, and simply patch it in whenever the trampoline is being populated, using the existing PLT support routines. Signed-off-by: Ard Biesheuvel Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman

arm64: module-plts: factor out PLT generation code for ftrace

2017-12-05T10:26:31Z

commit 7e8b9c1d2e2f5f45db7d40b50d14f606097c25de upstream. To allow the ftrace trampoline code to reuse the PLT entry routines, factor it out and move it into asm/module.h. Signed-off-by: Ard Biesheuvel Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman