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2019-04-06Merge tag 'trace-5.1-rc3' of ↵Linus Torvalds25-658/+192
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull syscall-get-arguments cleanup and fixes from Steven Rostedt: "Andy Lutomirski approached me to tell me that the syscall_get_arguments() implementation in x86 was horrible and gcc certainly gets it wrong. He said that since the tracepoints only pass in 0 and 6 for i and n repectively, it should be optimized for that case. Inspecting the kernel, I discovered that all users pass in 0 for i and only one file passing in something other than 6 for the number of arguments. That code happens to be my own code used for the special syscall tracing. That can easily be converted to just using 0 and 6 as well, and only copying what is needed. Which is probably the faster path anyway for that case. Along the way, a couple of real fixes came from this as the syscall_get_arguments() function was incorrect for csky and riscv. x86 has been optimized to for the new interface that removes the variable number of arguments, but the other architectures could still use some loving and take more advantage of the simpler interface" * tag 'trace-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: syscalls: Remove start and number from syscall_set_arguments() args syscalls: Remove start and number from syscall_get_arguments() args csky: Fix syscall_get_arguments() and syscall_set_arguments() riscv: Fix syscall_get_arguments() and syscall_set_arguments() tracing/syscalls: Pass in hardcoded 6 into syscall_get_arguments() ptrace: Remove maxargs from task_current_syscall()
2019-04-05KVM: x86: nVMX: fix x2APIC VTPR read interceptMarc Orr1-1/+1
Referring to the "VIRTUALIZING MSR-BASED APIC ACCESSES" chapter of the SDM, when "virtualize x2APIC mode" is 1 and "APIC-register virtualization" is 0, a RDMSR of 808H should return the VTPR from the virtual APIC page. However, for nested, KVM currently fails to disable the read intercept for this MSR. This means that a RDMSR exit takes precedence over "virtualize x2APIC mode", and KVM passes through L1's TPR to L2, instead of sourcing the value from L2's virtual APIC page. This patch fixes the issue by disabling the read intercept, in VMCS02, for the VTPR when "APIC-register virtualization" is 0. The issue described above and fix prescribed here, were verified with a related patch in kvm-unit-tests titled "Test VMX's virtualize x2APIC mode w/ nested". Signed-off-by: Marc Orr <marcorr@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Fixes: c992384bde84f ("KVM: vmx: speed up MSR bitmap merge") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-05KVM: x86: nVMX: close leak of L0's x2APIC MSRs (CVE-2019-3887)Marc Orr1-28/+44
The nested_vmx_prepare_msr_bitmap() function doesn't directly guard the x2APIC MSR intercepts with the "virtualize x2APIC mode" MSR. As a result, we discovered the potential for a buggy or malicious L1 to get access to L0's x2APIC MSRs, via an L2, as follows. 1. L1 executes WRMSR(IA32_SPEC_CTRL, 1). This causes the spec_ctrl variable, in nested_vmx_prepare_msr_bitmap() to become true. 2. L1 disables "virtualize x2APIC mode" in VMCS12. 3. L1 enables "APIC-register virtualization" in VMCS12. Now, KVM will set VMCS02's x2APIC MSR intercepts from VMCS12, and then set "virtualize x2APIC mode" to 0 in VMCS02. Oops. This patch closes the leak by explicitly guarding VMCS02's x2APIC MSR intercepts with VMCS12's "virtualize x2APIC mode" control. The scenario outlined above and fix prescribed here, were verified with a related patch in kvm-unit-tests titled "Add leak scenario to virt_x2apic_mode_test". Note, it looks like this issue may have been introduced inadvertently during a merge---see 15303ba5d1cd. Signed-off-by: Marc Orr <marcorr@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-05KVM: SVM: prevent DBG_DECRYPT and DBG_ENCRYPT overflowDavid Rientjes1-3/+9
This ensures that the address and length provided to DBG_DECRYPT and DBG_ENCRYPT do not cause an overflow. At the same time, pass the actual number of pages pinned in memory to sev_unpin_memory() as a cleanup. Reported-by: Cfir Cohen <cfir@google.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-05kvm: svm: fix potential get_num_contig_pages overflowDavid Rientjes1-5/+5
get_num_contig_pages() could potentially overflow int so make its type consistent with its usage. Reported-by: Cfir Cohen <cfir@google.com> Cc: stable@vger.kernel.org Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-05syscalls: Remove start and number from syscall_set_arguments() argsSteven Rostedt (VMware)19-296/+86
After removing the start and count arguments of syscall_get_arguments() it seems reasonable to remove them from syscall_set_arguments(). Note, as of today, there are no users of syscall_set_arguments(). But we are told that there will be soon. But for now, at least make it consistent with syscall_get_arguments(). Link: http://lkml.kernel.org/r/20190327222014.GA32540@altlinux.org Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Dave Martin <dave.martin@arm.com> Cc: "Dmitry V. Levin" <ldv@altlinux.org> Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86 Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-05syscalls: Remove start and number from syscall_get_arguments() argsSteven Rostedt (Red Hat)24-365/+105
At Linux Plumbers, Andy Lutomirski approached me and pointed out that the function call syscall_get_arguments() implemented in x86 was horribly written and not optimized for the standard case of passing in 0 and 6 for the starting index and the number of system calls to get. When looking at all the users of this function, I discovered that all instances pass in only 0 and 6 for these arguments. Instead of having this function handle different cases that are never used, simply rewrite it to return the first 6 arguments of a system call. This should help out the performance of tracing system calls by ptrace, ftrace and perf. Link: http://lkml.kernel.org/r/20161107213233.754809394@goodmis.org Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Dave Martin <dave.martin@arm.com> Cc: "Dmitry V. Levin" <ldv@altlinux.org> Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86 Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-05xen: Prevent buffer overflow in privcmd ioctlDan Carpenter1-0/+3
The "call" variable comes from the user in privcmd_ioctl_hypercall(). It's an offset into the hypercall_page[] which has (PAGE_SIZE / 32) elements. We need to put an upper bound on it to prevent an out of bounds access. Cc: stable@vger.kernel.org Fixes: 1246ae0bb992 ("xen: add variable hypercall caller") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-04-05KVM: PPC: Book3S: Protect memslots while validating user addressAlexey Kardashevskiy1-3/+3
Guest physical to user address translation uses KVM memslots and reading these requires holding the kvm->srcu lock. However recently introduced kvmppc_tce_validate() broke the rule (see the lockdep warning below). This moves srcu_read_lock(&vcpu->kvm->srcu) earlier to protect kvmppc_tce_validate() as well. ============================= WARNING: suspicious RCU usage 5.1.0-rc2-le_nv2_aikATfstn1-p1 #380 Not tainted ----------------------------- include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by qemu-system-ppc/8020: #0: 0000000094972fe9 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0xdc/0x850 [kvm] stack backtrace: CPU: 44 PID: 8020 Comm: qemu-system-ppc Not tainted 5.1.0-rc2-le_nv2_aikATfstn1-p1 #380 Call Trace: [c000003fece8f740] [c000000000bcc134] dump_stack+0xe8/0x164 (unreliable) [c000003fece8f790] [c000000000181be0] lockdep_rcu_suspicious+0x130/0x170 [c000003fece8f810] [c0000000000d5f50] kvmppc_tce_to_ua+0x280/0x290 [c000003fece8f870] [c00800001a7e2c78] kvmppc_tce_validate+0x80/0x1b0 [kvm] [c000003fece8f8e0] [c00800001a7e3fac] kvmppc_h_put_tce+0x94/0x3e4 [kvm] [c000003fece8f9a0] [c00800001a8baac4] kvmppc_pseries_do_hcall+0x30c/0xce0 [kvm_hv] [c000003fece8fa10] [c00800001a8bd89c] kvmppc_vcpu_run_hv+0x694/0xec0 [kvm_hv] [c000003fece8fae0] [c00800001a7d95dc] kvmppc_vcpu_run+0x34/0x48 [kvm] [c000003fece8fb00] [c00800001a7d56bc] kvm_arch_vcpu_ioctl_run+0x2f4/0x400 [kvm] [c000003fece8fb90] [c00800001a7c3618] kvm_vcpu_ioctl+0x460/0x850 [kvm] [c000003fece8fd00] [c00000000041c4f4] do_vfs_ioctl+0xe4/0x930 [c000003fece8fdb0] [c00000000041ce04] ksys_ioctl+0xc4/0x110 [c000003fece8fe00] [c00000000041ce78] sys_ioctl+0x28/0x80 [c000003fece8fe20] [c00000000000b5a4] system_call+0x5c/0x70 Fixes: 42de7b9e2167 ("KVM: PPC: Validate TCEs against preregistered memory page sizes", 2018-09-10) Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-04-05KVM: PPC: Book3S HV: Perserve PSSCR FAKE_SUSPEND bit on guest exitSuraj Jitindar Singh1-1/+3
There is a hardware bug in some POWER9 processors where a treclaim in fake suspend mode can cause an inconsistency in the XER[SO] bit across the threads of a core, the workaround being to force the core into SMT4 when doing the treclaim. The FAKE_SUSPEND bit (bit 10) in the PSSCR is used to control whether a thread is in fake suspend or real suspend. The important difference here being that thread reconfiguration is blocked in real suspend but not fake suspend mode. When we exit a guest which was in fake suspend mode, we force the core into SMT4 while we do the treclaim in kvmppc_save_tm_hv(). However on the new exit path introduced with the function kvmhv_run_single_vcpu() we restore the host PSSCR before calling kvmppc_save_tm_hv() which means that if we were in fake suspend mode we put the thread into real suspend mode when we clear the PSSCR[FAKE_SUSPEND] bit. This means that we block thread reconfiguration and the thread which is trying to get the core into SMT4 before it can do the treclaim spins forever since it itself is blocking thread reconfiguration. The result is that that core is essentially lost. This results in a trace such as: [ 93.512904] CPU: 7 PID: 13352 Comm: qemu-system-ppc Not tainted 5.0.0 #4 [ 93.512905] NIP: c000000000098a04 LR: c0000000000cc59c CTR: 0000000000000000 [ 93.512908] REGS: c000003fffd2bd70 TRAP: 0100 Not tainted (5.0.0) [ 93.512908] MSR: 9000000302883033 <SF,HV,VEC,VSX,FP,ME,IR,DR,RI,LE,TM[SE]> CR: 22222444 XER: 00000000 [ 93.512914] CFAR: c000000000098a5c IRQMASK: 3 [ 93.512915] PACATMSCRATCH: 0000000000000001 [ 93.512916] GPR00: 0000000000000001 c000003f6cc1b830 c000000001033100 0000000000000004 [ 93.512928] GPR04: 0000000000000004 0000000000000002 0000000000000004 0000000000000007 [ 93.512930] GPR08: 0000000000000000 0000000000000004 0000000000000000 0000000000000004 [ 93.512932] GPR12: c000203fff7fc000 c000003fffff9500 0000000000000000 0000000000000000 [ 93.512935] GPR16: 2000000000300375 000000000000059f 0000000000000000 0000000000000000 [ 93.512951] GPR20: 0000000000000000 0000000000080053 004000000256f41f c000003f6aa88ef0 [ 93.512953] GPR24: c000003f6aa89100 0000000000000010 0000000000000000 0000000000000000 [ 93.512956] GPR28: c000003f9e9a0800 0000000000000000 0000000000000001 c000203fff7fc000 [ 93.512959] NIP [c000000000098a04] pnv_power9_force_smt4_catch+0x1b4/0x2c0 [ 93.512960] LR [c0000000000cc59c] kvmppc_save_tm_hv+0x40/0x88 [ 93.512960] Call Trace: [ 93.512961] [c000003f6cc1b830] [0000000000080053] 0x80053 (unreliable) [ 93.512965] [c000003f6cc1b8a0] [c00800001e9cb030] kvmhv_p9_guest_entry+0x508/0x6b0 [kvm_hv] [ 93.512967] [c000003f6cc1b940] [c00800001e9cba44] kvmhv_run_single_vcpu+0x2dc/0xb90 [kvm_hv] [ 93.512968] [c000003f6cc1ba10] [c00800001e9cc948] kvmppc_vcpu_run_hv+0x650/0xb90 [kvm_hv] [ 93.512969] [c000003f6cc1bae0] [c00800001e8f620c] kvmppc_vcpu_run+0x34/0x48 [kvm] [ 93.512971] [c000003f6cc1bb00] [c00800001e8f2d4c] kvm_arch_vcpu_ioctl_run+0x2f4/0x400 [kvm] [ 93.512972] [c000003f6cc1bb90] [c00800001e8e3918] kvm_vcpu_ioctl+0x460/0x7d0 [kvm] [ 93.512974] [c000003f6cc1bd00] [c0000000003ae2c0] do_vfs_ioctl+0xe0/0x8e0 [ 93.512975] [c000003f6cc1bdb0] [c0000000003aeb24] ksys_ioctl+0x64/0xe0 [ 93.512978] [c000003f6cc1be00] [c0000000003aebc8] sys_ioctl+0x28/0x80 [ 93.512981] [c000003f6cc1be20] [c00000000000b3a4] system_call+0x5c/0x70 [ 93.512983] Instruction dump: [ 93.512986] 419dffbc e98c0000 2e8b0000 38000001 60000000 60000000 60000000 40950068 [ 93.512993] 392bffff 39400000 79290020 39290001 <7d2903a6> 60000000 60000000 7d235214 To fix this we preserve the PSSCR[FAKE_SUSPEND] bit until we call kvmppc_save_tm_hv() which will mean the core can get into SMT4 and perform the treclaim. Note kvmppc_save_tm_hv() clears the PSSCR[FAKE_SUSPEND] bit again so there is no need to explicitly do that. Fixes: 95a6432ce9038 ("KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests") Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-04-05xtensa: fix format string warning in init_pmdMax Filippov1-1/+1
Use %lu instead of %zu to fix the following warning introduced with recent memblock refactoring: xtensa/mm/mmu.c:36:9: warning: format '%zu' expects argument of type 'size_t', but argument 3 has type 'long unsigned int Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-04-05Merge tag 'riscv-for-linus-5.1-rc4' of ↵Linus Torvalds7-14/+37
git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux Pull RISC-V fixes from Palmer Dabbelt: "I dropped the ball a bit here: these patches should all probably have been part of rc2, but I wanted to get around to properly testing them in the various configurations (qemu32, qeum64, unleashed) first. Unfortunately I've been traveling and didn't have time to actually do that, but since these fix concrete bugs and pass my old set of tests I don't want to delay the fixes any longer. There are four independent fixes here: - A fix for the rv32 port that corrects the 64-bit user accesor's fixup label address. - A fix for a regression introduced during the merge window that broke medlow configurations at run time. This patch also includes a fix that disables ftrace for the same set of functions, which was found by inspection at the same time. - A modification of the memory map to avoid overlapping the FIXMAP and VMALLOC regions on systems with small memory maps. - A fix to the module handling code to use the correct syntax for probing Kconfig entries. These have passed my standard test flow, but I didn't have time to expand that testing like I said I would" * tag 'riscv-for-linus-5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: RISC-V: Use IS_ENABLED(CONFIG_CMODEL_MEDLOW) RISC-V: Fix FIXMAP_TOP to avoid overlap with VMALLOC area RISC-V: Always compile mm/init.c with cmodel=medany and notrace riscv: fix accessing 8-byte variable from RV32
2019-04-04xtensa: fix return_addressMax Filippov1-1/+5
return_address returns the address that is one level higher in the call stack than requested in its argument, because level 0 corresponds to its caller's return address. Use requested level as the number of stack frames to skip. This fixes the address reported by might_sleep and friends. Cc: stable@vger.kernel.org Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-04-04MIPS: generic: Add switchdev, pinctrl and fit to ocelot_defconfigHoratiu Vultur1-0/+8
Some of the configuration were not selected by default anymore, therefore enable them again. Also remove some configs which are used for MSCC Ocelot. Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: <alexandre.belloni@bootlin.com> Cc: <UNGLinuxDriver@microchip.com> Cc: <ralf@linux-mips.org> Cc: <jhogan@kernel.org> Cc: <linux-mips@vger.kernel.org> Cc: <linux-kernel@vger.kernel.org>
2019-04-04arm64: fix wrong check of on_sdei_stack in nmi contextWei Li1-0/+6
When doing unwind_frame() in the context of pseudo nmi (need enable CONFIG_ARM64_PSEUDO_NMI), reaching the bottom of the stack (fp == 0, pc != 0), function on_sdei_stack() will return true while the sdei acpi table is not inited in fact. This will cause a "NULL pointer dereference" oops when going on. Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Wei Li <liwei391@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-04-04csky: Fix syscall_get_arguments() and syscall_set_arguments()Dmitry V. Levin1-4/+6
C-SKY syscall arguments are located in orig_a0,a1,a2,a3,regs[0],regs[1] fields of struct pt_regs. Due to an off-by-one bug and a bug in pointer arithmetic syscall_get_arguments() was reading orig_a0,regs[1..5] fields instead. Likewise, syscall_set_arguments() was writing orig_a0,regs[1..5] fields instead. Link: http://lkml.kernel.org/r/20190329171230.GB32456@altlinux.org Fixes: 4859bfca11c7d ("csky: System Call") Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Will Drewry <wad@chromium.org> Cc: stable@vger.kernel.org # v4.20+ Tested-by: Guo Ren <ren_guo@c-sky.com> Acked-by: Guo Ren <ren_guo@c-sky.com> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-04riscv: Fix syscall_get_arguments() and syscall_set_arguments()Dmitry V. Levin1-5/+7
RISC-V syscall arguments are located in orig_a0,a1..a5 fields of struct pt_regs. Due to an off-by-one bug and a bug in pointer arithmetic syscall_get_arguments() was reading s3..s7 fields instead of a1..a5. Likewise, syscall_set_arguments() was writing s3..s7 fields instead of a1..a5. Link: http://lkml.kernel.org/r/20190329171221.GA32456@altlinux.org Fixes: e2c0cdfba7f69 ("RISC-V: User-facing API") Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Will Drewry <wad@chromium.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: linux-riscv@lists.infradead.org Cc: stable@vger.kernel.org # v4.15+ Acked-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-04arm/mach-at91/pm : fix possible object reference leakPeng Hao1-2/+4
of_find_device_by_node() takes a reference to the struct device when it finds a match via get_device. When returning error we should call put_device. Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn> Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
2019-04-04xtensa: fix initialization of pt_regs::syscall in start_threadMax Filippov1-9/+12
New pt_regs should indicate that there's no syscall, not that there's syscall #0. While at it wrap macro body in do/while and parenthesize macro arguments. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-04-04xtensa: use actual syscall number in do_syscall_trace_leaveMax Filippov1-0/+6
Syscall may alter pt_regs structure passed to it, resulting in a mismatch between syscall entry end syscall exit entries in the ftrace. Temporary restore syscall field of the pt_regs for the duration of do_syscall_trace_leave. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-04-03x86/perf/amd: Resolve NMI latency issues for active PMCsLendacky, Thomas1-1/+55
On AMD processors, the detection of an overflowed PMC counter in the NMI handler relies on the current value of the PMC. So, for example, to check for overflow on a 48-bit counter, bit 47 is checked to see if it is 1 (not overflowed) or 0 (overflowed). When the perf NMI handler executes it does not know in advance which PMC counters have overflowed. As such, the NMI handler will process all active PMC counters that have overflowed. NMI latency in newer AMD processors can result in multiple overflowed PMC counters being processed in one NMI and then a subsequent NMI, that does not appear to be a back-to-back NMI, not finding any PMC counters that have overflowed. This may appear to be an unhandled NMI resulting in either a panic or a series of messages, depending on how the kernel was configured. To mitigate this issue, add an AMD handle_irq callback function, amd_pmu_handle_irq(), that will invoke the common x86_pmu_handle_irq() function and upon return perform some additional processing that will indicate if the NMI has been handled or would have been handled had an earlier NMI not handled the overflowed PMC. Using a per-CPU variable, a minimum value of the number of active PMCs or 2 will be set whenever a PMC is active. This is used to indicate the possible number of NMIs that can still occur. The value of 2 is used for when an NMI does not arrive at the LAPIC in time to be collapsed into an already pending NMI. Each time the function is called without having handled an overflowed counter, the per-CPU value is checked. If the value is non-zero, it is decremented and the NMI indicates that it handled the NMI. If the value is zero, then the NMI indicates that it did not handle the NMI. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03x86/perf/amd: Resolve race condition when disabling PMCLendacky, Thomas1-3/+62
On AMD processors, the detection of an overflowed counter in the NMI handler relies on the current value of the counter. So, for example, to check for overflow on a 48 bit counter, bit 47 is checked to see if it is 1 (not overflowed) or 0 (overflowed). There is currently a race condition present when disabling and then updating the PMC. Increased NMI latency in newer AMD processors makes this race condition more pronounced. If the counter value has overflowed, it is possible to update the PMC value before the NMI handler can run. The updated PMC value is not an overflowed value, so when the perf NMI handler does run, it will not find an overflowed counter. This may appear as an unknown NMI resulting in either a panic or a series of messages, depending on how the kernel is configured. To eliminate this race condition, the PMC value must be checked after disabling the counter. Add an AMD function, amd_pmu_disable_all(), that will wait for the NMI handler to reset any active and overflowed counter after calling x86_pmu_disable_all(). Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03perf/x86/intel: Initialize TFA MSRPeter Zijlstra1-0/+6
Stephane reported that the TFA MSR is not initialized by the kernel, but the TFA bit could set by firmware or as a leftover from a kexec, which makes the state inconsistent. Reported-by: Stephane Eranian <eranian@google.com> Tested-by: Nelson DSouza <nelson.dsouza@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: tonyj@suse.com Link: https://lkml.kernel.org/r/20190321123849.GN6521@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBSStephane Eranian1-1/+1
When an event is programmed with attr.wakeup_events=N (N>0), it means the caller is interested in getting a user level notification after N samples have been recorded in the kernel sampling buffer. With precise events on Intel processors, the kernel uses PEBS. The kernel tries minimize sampling overhead by verifying if the event configuration is compatible with multi-entry PEBS mode. If so, the kernel is notified only when the buffer has reached its threshold. Other PEBS operates in single-entry mode, the kenrel is notified for each PEBS sample. The problem is that the current implementation look at frequency mode and event sample_type but ignores the wakeup_events field. Thus, it may not be possible to receive a notification after each precise event. This patch fixes this problem by disabling multi-entry PEBS if wakeup_events is non-zero. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: kan.liang@intel.com Link: https://lkml.kernel.org/r/20190306195048.189514-1-eranian@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-02ARC: [hsdk] Make it easier to add PAE40 region to DTBVineet Gupta1-6/+7
1. Bump top level address-cells/size-cells nodes to 2 (to ensure all down stream addresses are 64-bits, unless explicitly specified otherwise (in "soc" bus with all peripherals) 2. "memory" also specified with address/size 2 3. Add a commented reference for PAE40 region beyond 4GB physical address space Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2019-04-02ARC: PAE40: don't panic and instead turn off hw iocVineet Gupta1-15/+16
HSDK currently panics when built for HIGHMEM/ARC_HAS_PAE40 because ioc is enabled with default which doesn't work for the 2 non contiguous memory nodes. So get PAE working by disabling ioc instead. Tested with !PAE40 by forcing @ioc_enable=0 and running the glibc testsuite over ssh Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2019-04-01x86/resctrl: Fix typos in the mba_sc mount optionXiaochen Shen1-3/+3
The user can control the MBA memory bandwidth in MBps (Mega Bytes per second) units of the MBA Software Controller (mba_sc) by using the "mba_MBps" mount option. For details, see Documentation/x86/resctrl_ui.txt. However, commit 23bf1b6be9c2 ("kernfs, sysfs, cgroup, intel_rdt: Support fs_context") changed the mount option name from "mba_MBps" to "mba_mpbs" by mistake. Change it back from to "mba_MBps" because it is user-visible, and correct "Opt_mba_mpbs" spelling to "Opt_mba_mbps". [ bp: massage commit message. ] Fixes: 23bf1b6be9c2 ("kernfs, sysfs, cgroup, intel_rdt: Support fs_context") Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: dhowells@redhat.com Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: pei.p.jia@intel.com Cc: Reinette Chatre <reinette.chatre@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/1553896238-22130-1-git-send-email-xiaochen.shen@intel.com
2019-04-01Merge commit '7d56bedb2730dc2ea8abf0fd7240ee99ecfee3c9' into omap-for-v5.1/fixesTony Lindgren1-2/+2
2019-04-01powerpc/32: Fix early boot failure with RTAS built-inChristophe Leroy1-8/+0
Commit 0df977eafc79 ("powerpc/6xx: Don't use SPRN_SPRG2 for storing stack pointer while in RTAS") changes the code to use a field in thread struct to store the stack pointer while in RTAS instead of using SPRN_SPRG2. It therefore converts all places which were manipulating SPRN_SPRG2 to use that field. During early startup, the zeroing of SPRN_SPRG2 has been replaced by a zeroing of that field in thread struct. But at least in start_here, that's done wrongly because it used the physical address of the fields while MMU is on at that time. So the virtual address of the field should be used instead, but in the meantime, thread struct has already been zeroed and initialised so we can just drop this initialisation. Reported-by: Larry Finger <Larry.Finger@lwfinger.net> Fixes: 0df977eafc79 ("powerpc/6xx: Don't use SPRN_SPRG2 for storing stack pointer while in RTAS") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Tested-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-03-31Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds45-78/+181
Pull KVM fixes from Paolo Bonzini: "A collection of x86 and ARM bugfixes, and some improvements to documentation. On top of this, a cleanup of kvm_para.h headers, which were exported by some architectures even though they not support KVM at all. This is responsible for all the Kbuild changes in the diffstat" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (28 commits) Documentation: kvm: clarify KVM_SET_USER_MEMORY_REGION KVM: doc: Document the life cycle of a VM and its resources KVM: selftests: complete IO before migrating guest state KVM: selftests: disable stack protector for all KVM tests KVM: selftests: explicitly disable PIE for tests KVM: selftests: assert on exit reason in CR4/cpuid sync test KVM: x86: update %rip after emulating IO x86/kvm/hyper-v: avoid spurious pending stimer on vCPU init kvm/x86: Move MSR_IA32_ARCH_CAPABILITIES to array emulated_msrs KVM: x86: Emulate MSR_IA32_ARCH_CAPABILITIES on AMD hosts kvm: don't redefine flags as something else kvm: mmu: Used range based flushing in slot_handle_level_range KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supported KVM: x86: remove check on nr_mmu_pages in kvm_arch_commit_memory_region() kvm: nVMX: Add a vmentry check for HOST_SYSENTER_ESP and HOST_SYSENTER_EIP fields KVM: SVM: Workaround errata#1096 (insn_len maybe zero on SMAP violation) KVM: Reject device ioctls from processes other than the VM's creator KVM: doc: Fix incorrect word ordering regarding supported use of APIs KVM: x86: fix handling of role.cr4_pae and rename it to 'gpte_size' KVM: nVMX: Do not inherit quadrant and invalid for the root shadow EPT ...
2019-03-31Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds8-22/+19
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A pile of x86 updates: - Prevent exceeding he valid physical address space in the /dev/mem limit checks. - Move all header content inside the header guard to prevent compile failures. - Fix the bogus __percpu annotation in this_cpu_has() which makes sparse very noisy. - Disable switch jump tables completely when retpolines are enabled. - Prevent leaking the trampoline address" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/realmode: Make set_real_mode_mem() static inline x86/cpufeature: Fix __percpu annotation in this_cpu_has() x86/mm: Don't exceed the valid physical address space x86/retpolines: Disable switch jump tables when retpolines are enabled x86/realmode: Don't leak the trampoline kernel address x86/boot: Fix incorrect ifdeffery scope x86/resctrl: Remove unused variable
2019-03-31Merge branch 'smp-urgent-for-linus' of ↵Linus Torvalds1-7/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull CPU hotplug fixes from Thomas Gleixner: "Two SMT/hotplug related fixes: - Prevent crash when HOTPLUG_CPU is disabled and the CPU bringup aborts. This is triggered with the 'nosmt' command line option, but can happen by any abort condition. As the real unplug code is not compiled in, prevent the fail by keeping the CPU in zombie state. - Enforce HOTPLUG_CPU for SMP on x86 to avoid the above situation completely. With 'nosmt' being a popular option it's required to unplug the half brought up sibling CPUs (due to the MCE wreckage) completely" * 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/smp: Enforce CONFIG_HOTPLUG_CPU when SMP=y cpu/hotplug: Prevent crash when CPU bringup fails on CONFIG_HOTPLUG_CPU=n
2019-03-31Merge tag 'powerpc-5.1-4' of ↵Linus Torvalds3-13/+32
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "Three non-regression fixes. - Our optimised memcmp could read past the end of one of the buffers and potentially trigger a page fault leading to an oops. - Some of our code to read energy management data on PowerVM had an endian bug leading to bogus results. - When reporting a machine check exception we incorrectly reported TLB multihits as D-Cache multhits due to a missing entry in the array of causes. Thanks to: Chandan Rajendra, Gautham R. Shenoy, Mahesh Salgaonkar, Segher Boessenkool, Vaidyanathan Srinivasan" * tag 'powerpc-5.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/pseries/mce: Fix misleading print for TLB mutlihit powerpc/pseries/energy: Use OF accessor functions to read ibm,drc-indexes powerpc/64: Fix memcmp reading past the end of src/dest
2019-03-30Merge tag 'arm64-fixes' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fix from Catalin Marinas: "Use memblock_alloc() instead of memblock_alloc_low() in request_standard_resources(), the latter being limited to the low 4G memory range on arm64" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: replace memblock_alloc_low with memblock_alloc
2019-03-29x86/realmode: Make set_real_mode_mem() static inlineMatteo Croce3-10/+7
Remove the unused @size argument and move it into a header file, so it can be inlined. [ bp: Massage. ] Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-efi <linux-efi@vger.kernel.org> Cc: platform-driver-x86@vger.kernel.org Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190328114233.27835-1-mcroce@redhat.com
2019-03-29s390/mem_detect: Use IS_ENABLED(CONFIG_BLK_DEV_INITRD)Joe Perches1-1/+1
IS_ENABLED should generally use CONFIG_ prefaced symbols and it doesn't appear as if there is a BLK_DEV_INITRD define. Cc: <stable@vger.kernel.org> # 4.20 Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-29RISC-V: Use IS_ENABLED(CONFIG_CMODEL_MEDLOW)Joe Perches1-1/+1
IS_ENABLED should generally use CONFIG_ prefaced symbols and it doesn't appear as if there is a CMODEL_MEDLOW define. Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-29RISC-V: Fix FIXMAP_TOP to avoid overlap with VMALLOC areaAnup Patel1-1/+1
The FIXMAP area overlaps with VMALLOC area in Linux-5.1-rc1 hence we get below warning in Linux RISC-V 32bit kernel. This warning does not show-up in Linux RISC-V 64bit kernel due to large VMALLOC area. WARNING: CPU: 0 PID: 22 at mm/vmalloc.c:150 vmap_page_range_noflush+0x134/0x15c Modules linked in: CPU: 0 PID: 22 Comm: kworker/0:1 Not tainted 5.1.0-rc1-00005-gebc2f658040e #1 Workqueue: events pcpu_balance_workfn Call Trace: [<c002b950>] walk_stackframe+0x0/0xa0 [<c002baac>] show_stack+0x28/0x32 [<c0587354>] dump_stack+0x62/0x7e [<c002fdee>] __warn+0x98/0xce [<c002fe52>] warn_slowpath_null+0x2e/0x3c [<c00e71ce>] vmap_page_range_noflush+0x134/0x15c [<c00e7886>] map_kernel_range_noflush+0xc/0x14 [<c00d54b8>] pcpu_populate_chunk+0x19e/0x236 [<c00d610e>] pcpu_balance_workfn+0x448/0x464 [<c00408d6>] process_one_work+0x16c/0x2ea [<c0040b46>] worker_thread+0xf2/0x3b2 [<c004519a>] kthread+0xce/0xdc [<c002a974>] ret_from_exception+0x0/0xc This patch fixes above warning by placing FIXMAP area below VMALLOC area. Fixes: f2c17aabc917 ("RISC-V: Implement compile-time fixed mappings") Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-03-29powerpc/pseries/mce: Fix misleading print for TLB mutlihitMahesh Salgaonkar1-0/+1
On pseries, TLB multihit are reported as D-Cache Multihit. This is because the wrongly populated mc_err_types[] array. Per PAPR, TLB error type is 0x04 and mc_err_types[4] points to "D-Cache" instead of "TLB" string. Fixup the mc_err_types[] array. Machine check error type per PAPR: 0x00 = Uncorrectable Memory Error (UE) 0x01 = SLB error 0x02 = ERAT Error 0x04 = TLB error 0x05 = D-Cache error 0x07 = I-Cache error Fixes: 8f0b80561f21 ("powerpc/pseries: Display machine check error details.") Cc: stable@vger.kernel.org # v4.20+ Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-03-28MIPS: SGI-IP27: Fix use of unchecked pointer in shutdown_bridge_irqThomas Bogendoerfer1-2/+1
smatch complaint: arch/mips/sgi-ip27/ip27-irq.c:123 shutdown_bridge_irq() warn: variable dereferenced before check 'hd' (see line 121) Fix it by removing local variable and use hd->pin directly. Fixes: 69a07a41d908 ("MIPS: SGI-IP27: rework HUB interrupts") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <jhogan@kernel.org> Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org
2019-03-28MIPS: KGDB: fix kgdb support for SMP platforms.Chong Qiao1-1/+2
KGDB_call_nmi_hook is called by other cpu through smp call. MIPS smp call is processed in ipi irq handler and regs is saved in handle_int. So kgdb_call_nmi_hook get regs by get_irq_regs and regs will be passed to kgdb_cpu_enter. Signed-off-by: Chong Qiao <qiaochong@loongson.cn> Reviewed-by: Douglas Anderson <dianders@chromium.org> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <jhogan@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: QiaoChong <qiaochong@loongson.cn>
2019-03-28Merge tag 'kvmarm-fixes-for-5.1' of ↵Paolo Bonzini4-3/+27
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master KVM/ARM fixes for 5.1 - Fix THP handling in the presence of pre-existing PTEs - Honor request for PTE mappings even when THPs are available - GICv4 performance improvement - Take the srcu lock when writing to guest-controlled ITS data structures - Reset the virtual PMU in preemptible context - Various cleanups
2019-03-28KVM: x86: update %rip after emulating IOSean Christopherson2-10/+27
Most (all?) x86 platforms provide a port IO based reset mechanism, e.g. OUT 92h or CF9h. Userspace may emulate said mechanism, i.e. reset a vCPU in response to KVM_EXIT_IO, without explicitly announcing to KVM that it is doing a reset, e.g. Qemu jams vCPU state and resumes running. To avoid corruping %rip after such a reset, commit 0967b7bf1c22 ("KVM: Skip pio instruction when it is emulated, not executed") changed the behavior of PIO handlers, i.e. today's "fast" PIO handling to skip the instruction prior to exiting to userspace. Full emulation doesn't need such tricks becase re-emulating the instruction will naturally handle %rip being changed to point at the reset vector. Updating %rip prior to executing to userspace has several drawbacks: - Userspace sees the wrong %rip on the exit, e.g. if PIO emulation fails it will likely yell about the wrong address. - Single step exits to userspace for are effectively dropped as KVM_EXIT_DEBUG is overwritten with KVM_EXIT_IO. - Behavior of PIO emulation is different depending on whether it goes down the fast path or the slow path. Rather than skip the PIO instruction before exiting to userspace, snapshot the linear %rip and cancel PIO completion if the current value does not match the snapshot. For a 64-bit vCPU, i.e. the most common scenario, the snapshot and comparison has negligible overhead as VMCS.GUEST_RIP will be cached regardless, i.e. there is no extra VMREAD in this case. All other alternatives to snapshotting the linear %rip that don't rely on an explicit reset announcenment suffer from one corner case or another. For example, canceling PIO completion on any write to %rip fails if userspace does a save/restore of %rip, and attempting to avoid that issue by canceling PIO only if %rip changed then fails if PIO collides with the reset %rip. Attempting to zero in on the exact reset vector won't work for APs, which means adding more hooks such as the vCPU's MP_STATE, and so on and so forth. Checking for a linear %rip match technically suffers from corner cases, e.g. userspace could theoretically rewrite the underlying code page and expect a different instruction to execute, or the guest hardcodes a PIO reset at 0xfffffff0, but those are far, far outside of what can be considered normal operation. Fixes: 432baf60eee3 ("KVM: VMX: use kvm_fast_pio_in for handling IN I/O") Cc: <stable@vger.kernel.org> Reported-by: Jim Mattson <jmattson@google.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-28x86/kvm/hyper-v: avoid spurious pending stimer on vCPU initVitaly Kuznetsov1-2/+7
When userspace initializes guest vCPUs it may want to zero all supported MSRs including Hyper-V related ones including HV_X64_MSR_STIMERn_CONFIG/ HV_X64_MSR_STIMERn_COUNT. With commit f3b138c5d89a ("kvm/x86: Update SynIC timers on guest entry only") we began doing stimer_mark_pending() unconditionally on every config change. The issue I'm observing manifests itself as following: - Qemu writes 0 to STIMERn_{CONFIG,COUNT} MSRs and marks all stimers as pending in stimer_pending_bitmap, arms KVM_REQ_HV_STIMER; - kvm_hv_has_stimer_pending() starts returning true; - kvm_vcpu_has_events() starts returning true; - kvm_arch_vcpu_runnable() starts returning true; - when kvm_arch_vcpu_ioctl_run() gets into (vcpu->arch.mp_state == KVM_MP_STATE_UNINITIALIZED) case: - kvm_vcpu_block() gets in 'kvm_vcpu_check_block(vcpu) < 0' and returns immediately, avoiding normal wait path; - -EAGAIN is returned from kvm_arch_vcpu_ioctl_run() immediately forcing userspace to retry. So instead of normal wait path we get a busy loop on all secondary vCPUs before they get INIT signal. This seems to be undesirable, especially given that this happens even when Hyper-V extensions are not used. Generally, it seems to be pointless to mark an stimer as pending in stimer_pending_bitmap and arm KVM_REQ_HV_STIMER as the only thing kvm_hv_process_stimers() will do is clear the corresponding bit. We may just not mark disabled timers as pending instead. Fixes: f3b138c5d89a ("kvm/x86: Update SynIC timers on guest entry only") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-28kvm/x86: Move MSR_IA32_ARCH_CAPABILITIES to array emulated_msrsXiaoyao Li1-1/+2
Since MSR_IA32_ARCH_CAPABILITIES is emualted unconditionally even if host doesn't suppot it. We should move it to array emulated_msrs from arry msrs_to_save, to report to userspace that guest support this msr. Signed-off-by: Xiaoyao Li <xiaoyao.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-28KVM: x86: Emulate MSR_IA32_ARCH_CAPABILITIES on AMD hostsSean Christopherson4-14/+13
The CPUID flag ARCH_CAPABILITIES is unconditioinally exposed to host userspace for all x86 hosts, i.e. KVM advertises ARCH_CAPABILITIES regardless of hardware support under the pretense that KVM fully emulates MSR_IA32_ARCH_CAPABILITIES. Unfortunately, only VMX hosts handle accesses to MSR_IA32_ARCH_CAPABILITIES (despite KVM_GET_MSRS also reporting MSR_IA32_ARCH_CAPABILITIES for all hosts). Move the MSR_IA32_ARCH_CAPABILITIES handling to common x86 code so that it's emulated on AMD hosts. Fixes: 1eaafe91a0df4 ("kvm: x86: IA32_ARCH_CAPABILITIES is always supported") Cc: stable@vger.kernel.org Reported-by: Xiaoyao Li <xiaoyao.li@linux.intel.com> Cc: Jim Mattson <jmattson@google.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-28kvm: mmu: Used range based flushing in slot_handle_level_rangeBen Gardon1-2/+5
Replace kvm_flush_remote_tlbs with kvm_flush_remote_tlbs_with_address in slot_handle_level_range. When range based flushes are not enabled kvm_flush_remote_tlbs_with_address falls back to kvm_flush_remote_tlbs. This changes the behavior of many functions that indirectly use slot_handle_level_range, iff the range based flushes are enabled. The only potential problem I see with this is that kvm->tlbs_dirty will be cleared less often, however the only caller of slot_handle_level_range that checks tlbs_dirty is kvm_mmu_notifier_invalidate_range_start which checks it and does a kvm_flush_remote_tlbs after calling kvm_unmap_hva_range anyway. Tested: Ran all kvm-unit-tests on a Intel Haswell machine with and without this patch. The patch introduced no new failures. Signed-off-by: Ben Gardon <bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-28KVM: export <linux/kvm_para.h> and <asm/kvm_para.h> iif KVM is supportedMasahiro Yamada32-20/+16
I do not see any consistency about headers_install of <linux/kvm_para.h> and <asm/kvm_para.h>. According to my analysis of Linux 5.1-rc1, there are 3 groups: [1] Both <linux/kvm_para.h> and <asm/kvm_para.h> are exported alpha, arm, hexagon, mips, powerpc, s390, sparc, x86 [2] <asm/kvm_para.h> is exported, but <linux/kvm_para.h> is not arc, arm64, c6x, h8300, ia64, m68k, microblaze, nios2, openrisc, parisc, sh, unicore32, xtensa [3] Neither <linux/kvm_para.h> nor <asm/kvm_para.h> is exported csky, nds32, riscv This does not match to the actual KVM support. At least, [2] is half-baked. Nor do arch maintainers look like they care about this. For example, commit 0add53713b1c ("microblaze: Add missing kvm_para.h to Kbuild") exported <asm/kvm_para.h> to user-space in order to fix an in-kernel build error. We have two ways to make this consistent: [A] export both <linux/kvm_para.h> and <asm/kvm_para.h> for all architectures, irrespective of the KVM support [B] Match the header export of <linux/kvm_para.h> and <asm/kvm_para.h> to the KVM support My first attempt was [A] because the code looks cleaner, but Paolo suggested [B]. So, this commit goes with [B]. For most architectures, <asm/kvm_para.h> was moved to the kernel-space. I changed include/uapi/linux/Kbuild so that it checks generated asm/kvm_para.h as well as check-in ones. After this commit, there will be two groups: [1] Both <linux/kvm_para.h> and <asm/kvm_para.h> are exported arm, arm64, mips, powerpc, s390, x86 [2] Neither <linux/kvm_para.h> nor <asm/kvm_para.h> is exported alpha, arc, c6x, csky, h8300, hexagon, ia64, m68k, microblaze, nds32, nios2, openrisc, parisc, riscv, sh, sparc, unicore32, xtensa Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-28KVM: x86: remove check on nr_mmu_pages in kvm_arch_commit_memory_region()Wei Yang3-8/+4
* nr_mmu_pages would be non-zero only if kvm->arch.n_requested_mmu_pages is non-zero. * nr_mmu_pages is always non-zero, since kvm_mmu_calculate_mmu_pages() never return zero. Based on these two reasons, we can merge the two *if* clause and use the return value from kvm_mmu_calculate_mmu_pages() directly. This simplify the code and also eliminate the possibility for reader to believe nr_mmu_pages would be zero. Signed-off-by: Wei Yang <richard.weiyang@gmail.com> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-28kvm: nVMX: Add a vmentry check for HOST_SYSENTER_ESP and HOST_SYSENTER_EIP ↵Krish Sadhukhan1-0/+5
fields According to section "Checks on VMX Controls" in Intel SDM vol 3C, the following check is performed on vmentry of L2 guests: On processors that support Intel 64 architecture, the IA32_SYSENTER_ESP field and the IA32_SYSENTER_EIP field must each contain a canonical address. Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>