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2021-02-12Merge branch 'x86/paravirt' into x86/entryIngo Molnar204-1000/+1297
Merge in the recent paravirt changes to resolve conflicts caused by objtool annotations. Conflicts: arch/x86/xen/xen-asm.S Signed-off-by: Ingo Molnar <mingo@kernel.org>
2021-02-11x86/softirq/64: Inline do_softirq_own_stack()Thomas Gleixner3-7/+12
There is no reason to have this as a seperate function for a single caller. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002513.382806685@linutronix.de
2021-02-11softirq: Move do_softirq_own_stack() to generic asm headerThomas Gleixner7-0/+7
To avoid include recursion hell move the do_softirq_own_stack() related content into a generic asm header and include it from all places in arch/ which need the prototype. This allows architectures to provide an inline implementation of do_softirq_own_stack() without introducing a lot of #ifdeffery all over the place. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002513.289960691@linutronix.de
2021-02-11softirq: Move __ARCH_HAS_DO_SOFTIRQ to KconfigThomas Gleixner13-11/+12
To prepare for inlining do_softirq_own_stack() replace __ARCH_HAS_DO_SOFTIRQ with a Kconfig switch and select it in the affected architectures. This allows in the next step to move the function prototype and the inline stub into a seperate asm-generic header file which is required to avoid include recursion. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002513.181713427@linutronix.de
2021-02-11x86: Select CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACKThomas Gleixner3-12/+10
Now that all invocations of irq_exit_rcu() happen on the irq stack, turn on CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK which causes the core code to invoke __do_softirq() directly without going through do_softirq_own_stack(). That means do_softirq_own_stack() is only invoked from task context which means it can't be on the irq stack. Remove the conditional from run_softirq_on_irqstack_cond() and rename the function accordingly. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002513.068033456@linutronix.de
2021-02-11x86/softirq: Remove indirection in do_softirq_own_stack()Thomas Gleixner3-76/+17
Use the new inline stack switching and remove the old ASM indirect call implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002512.972714001@linutronix.de
2021-02-11x86/entry: Use run_sysvec_on_irqstack_cond() for XEN upcallThomas Gleixner1-13/+6
To avoid yet another macro implementation reuse the existing run_sysvec_on_irqstack_cond() and move the set_irq_regs() handling into the called function. Makes the code even simpler. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002512.869753106@linutronix.de
2021-02-11x86/entry: Convert device interrupts to inline stack switchingThomas Gleixner4-34/+36
Convert device interrupts to inline stack switching by replacing the existing macro implementation with the new inline version. Tweak the function signature of the actual handler function to have the vector argument as u32. That allows the inline macro to avoid extra intermediates and lets the compiler be smarter about the whole thing. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002512.769728139@linutronix.de
2021-02-11x86/entry: Convert system vectors to irq stack macroThomas Gleixner3-30/+66
To inline the stack switching and to prepare for enabling CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK provide a macro template for system vectors and device interrupts and convert the system vectors over to it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002512.676197354@linutronix.de
2021-02-11x86/irq: Provide macro for inlining irq stack switchingThomas Gleixner1-0/+98
The effort to make the ASM entry code slim and unified moved the irq stack switching out of the low level ASM code so that the whole return from interrupt work and state handling can be done in C and the ASM code just handles the low level details of entry and exit. This ended up being a suboptimal implementation for various reasons (including tooling). The main pain points are: - The indirect call which is expensive thanks to retpoline - The inability to stay on the irq stack for softirq processing on return from interrupt - The fact that the stack switching code ends up being an easy to target exploit gadget. Prepare for inlining the stack switching logic into the C entry points by providing a ASM macro which contains the guts of the switching mechanism: 1) Store RSP at the top of the irq stack 2) Switch RSP to the irq stack 3) Invoke code 4) Pop the original RSP back Document the unholy asm() logic while at it to reduce the amount of head scratching required a half year from now. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002512.578371068@linutronix.de
2021-02-11x86/apic: Split out spurious handling codeThomas Gleixner1-12/+19
sysvec_spurious_apic_interrupt() calls into the handling body of __spurious_interrupt() which is not obvious as that function is declared inside the DEFINE_IDTENTRY_IRQ(spurious_interrupt) macro. As __spurious_interrupt() is currently always inlined this ends up with two copies of the same code for no reason. Split the handling function out and invoke it from both entry points. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002512.469379641@linutronix.de
2021-02-11x86/irq/64: Adjust the per CPU irq stack pointer by 8Thomas Gleixner5-16/+27
The per CPU hardirq_stack_ptr contains the pointer to the irq stack in the form that it is ready to be assigned to [ER]SP so that the first push ends up on the top entry of the stack. But the stack switching on 64 bit has the following rules: 1) Store the current stack pointer (RSP) in the top most stack entry to allow the unwinder to link back to the previous stack 2) Set RSP to the top most stack entry 3) Invoke functions on the irq stack 4) Pop RSP from the top most stack entry (stored in #1) so it's back to the original stack. That requires all stack switching code to decrement the stored pointer by 8 in order to be able to store the current RSP and then set RSP to that location. That's a pointless exercise. Do the -8 adjustment right when storing the pointer and make the data type a void pointer to avoid confusion vs. the struct irq_stack data type which is on 64bit only used to declare the backing store. Move the definition next to the inuse flag so they likely end up in the same cache line. Sticking them into a struct to enforce it is a seperate change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002512.354260928@linutronix.de
2021-02-11x86/irq: Sanitize irq stack trackingThomas Gleixner4-10/+10
The recursion protection for hard interrupt stacks is an unsigned int per CPU variable initialized to -1 named __irq_count. The irq stack switching is only done when the variable is -1, which creates worse code than just checking for 0. When the stack switching happens it uses this_cpu_add/sub(1), but there is no reason to do so. It simply can use straight writes. This is a historical leftover from the low level ASM code which used inc and jz to make a decision. Rename it to hardirq_stack_inuse, make it a bool and use plain stores. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210210002512.228830141@linutronix.de
2021-02-11x86/entry: Fix instrumentation annotationThomas Gleixner1-1/+1
Embracing a callout into instrumentation_begin() / instrumentation_begin() does not really make sense. Make the latter instrumentation_end(). Fixes: 2f6474e4636b ("x86/entry: Switch XEN/PV hypercall entry to IDTENTRY") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210210002512.106502464@linutronix.de
2021-02-10Merge branch 'objtool/core' into x86/entryThomas Gleixner17-153/+207
to base the irq stack modifications on.
2021-02-10x86/unwind/orc: Change REG_SP_INDIRECTPeter Zijlstra1-1/+4
Currently REG_SP_INDIRECT is unused but means (%rsp + offset), change it to mean (%rsp) + offset. The reason is that we're going to swizzle stack in the middle of a C function with non-trivial stack footprint. This means that when the unwinder finds the ToS, it needs to dereference it (%rsp) and then add the offset to the next frame, resulting in: (%rsp) + offset This is somewhat unfortunate, since REG_BP_INDIRECT is used (by DRAP) and thus needs to retain the current (%rbp + offset). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
2021-02-10x86/pv: Rework arch_local_irq_restore() to not use popfJuergen Gross10-93/+8
POPF is a rather expensive operation, so don't use it for restoring irq flags. Instead, test whether interrupts are enabled in the flags parameter and enable interrupts via STI in that case. This results in the restore_fl paravirt op to be no longer needed. Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210120135555.32594-7-jgross@suse.com
2021-02-10x86/xen: Drop USERGS_SYSRET64 paravirt callJuergen Gross10-61/+8
USERGS_SYSRET64 is used to return from a syscall via SYSRET, but a Xen PV guest will nevertheless use the IRET hypercall, as there is no sysret PV hypercall defined. So instead of testing all the prerequisites for doing a sysret and then mangling the stack for Xen PV again for doing an iret just use the iret exit from the beginning. This can easily be done via an ALTERNATIVE like it is done for the sysenter compat case already. It should be noted that this drops the optimization in Xen for not restoring a few registers when returning to user mode, but it seems as if the saved instructions in the kernel more than compensate for this drop (a kernel build in a Xen PV guest was slightly faster with this patch applied). While at it remove the stale sysret32 remnants. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210120135555.32594-6-jgross@suse.com
2021-02-10x86/pv: Switch SWAPGS to ALTERNATIVEJuergen Gross8-47/+13
SWAPGS is used only for interrupts coming from user mode or for returning to user mode. So there is no reason to use the PARAVIRT framework, as it can easily be replaced by an ALTERNATIVE depending on X86_FEATURE_XENPV. There are several instances using the PV-aware SWAPGS macro in paths which are never executed in a Xen PV guest. Replace those with the plain swapgs instruction. For SWAPGS_UNSAFE_STACK the same applies. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210120135555.32594-5-jgross@suse.com
2021-02-10x86/xen: Use specific Xen pv interrupt entry for DFJuergen Gross3-3/+12
Xen PV guests don't use IST. For double fault interrupts, switch to the same model as NMI. Correct a typo in a comment while copying it. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210120135555.32594-4-jgross@suse.com
2021-02-10x86/xen: Use specific Xen pv interrupt entry for MCEJuergen Gross3-2/+19
Xen PV guests don't use IST. For machine check interrupts, switch to the same model as debug interrupts. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210120135555.32594-3-jgross@suse.com
2021-02-07Merge tag 'core_urgent_for_v5.11_rc7' of ↵Linus Torvalds2-4/+8
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull syscall entry fixes from Borislav Petkov: - For syscall user dispatch, separate prctl operation from syscall redirection range specification before the API has been made official in 5.11. - Ensure tasks using the generic syscall code do trap after returning from a syscall when single-stepping is requested. * tag 'core_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: entry: Use different define for selector variable in SUD entry: Ensure trap after single-step on system call return
2021-02-07Merge tag 'x86_urgent_for_v5.11_rc7' of ↵Linus Torvalds9-55/+76
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: "I hope this is the last batch of x86/urgent updates for this round: - Remove superfluous EFI PGD range checks which lead to those assertions failing with certain kernel configs and LLVM. - Disable setting breakpoints on facilities involved in #DB exception handling to avoid infinite loops. - Add extra serialization to non-serializing MSRs (IA32_TSC_DEADLINE and x2 APIC MSRs) to adhere to SDM's recommendation and avoid any theoretical issues. - Re-add the EPB MSR reading on turbostat so that it works on older kernels which don't have the corresponding EPB sysfs file. - Add Alder Lake to the list of CPUs which support split lock. - Fix %dr6 register handling in order to be able to set watchpoints with gdb again. - Disable CET instrumentation in the kernel so that gcc doesn't add ENDBR64 to kernel code and thus confuse tracing" * tag 'x86_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/efi: Remove EFI PGD build time checks x86/debug: Prevent data breakpoints on cpu_dr7 x86/debug: Prevent data breakpoints on __per_cpu_offset x86/apic: Add extra serialization for non-serializing MSRs tools/power/turbostat: Fallback to an MSR read for EPB x86/split_lock: Enable the split lock feature on another Alder Lake CPU x86/debug: Fix DR6 handling x86/build: Disable CET instrumentation in the kernel
2021-02-07Merge tag 'kbuild-fixes-v5.11-2' of ↵Linus Torvalds2-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - Use the 'python3' command to invoke python scripts because some distributions do not provide the 'python' command any more. - Clean-up and update documents - Use pkg-config to search libcrypto - Fix duplicated debug flags - Ignore some more stubs in scripts/kallsyms.c * tag 'kbuild-fixes-v5.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kallsyms: fix nonconverging kallsyms table with lld kbuild: fix duplicated flags in DEBUG_CFLAGS scripts/clang-tools: switch explicitly to Python 3 kbuild: remove PYTHON variable Documentation/llvm: Add a section about supported architectures Revert "checkpatch: add check for keyword 'boolean' in Kconfig definitions" scripts: use pkg-config to locate libcrypto kconfig: mconf: fix HOSTCC call doc: gcc-plugins: update gcc-plugins.rst kbuild: simplify GCC_PLUGINS enablement in dummy-tools/gcc Documentation/Kbuild: Remove references to gcc-plugin.sh scripts: switch explicitly to Python 3
2021-02-07Merge tag 'riscv-for-linus-5.11-rc7' of ↵Linus Torvalds4-5/+12
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: "A handful of fixes for this week: - A fix to avoid evalating the VA twice in virt_addr_valid, which fixes some WARNs under DEBUG_VIRTUAL. - Two fixes related to STRICT_KERNEL_RWX: one that fixes some permissions when strict is disabled, and one to fix some alignment issues when strict is enabled. - A fix to disallow the selection of MAXPHYSMEM_2GB on RV32, which isn't valid any more but may still show up in some oldconfigs. We still have the HiFive Unleashed ethernet phy reset regression, so there will likely be something coming next week" * tag 'riscv-for-linus-5.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: RISC-V: Define MAXPHYSMEM_1GB only for RV32 riscv: Align on L1_CACHE_BYTES when STRICT_KERNEL_RWX RISC-V: Fix .init section permission update riscv: virt_addr_valid must check the address belongs to linear mapping
2021-02-07Merge tag 'powerpc-5.11-7' of ↵Linus Torvalds8-21/+23
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - A fix for a change we made to __kernel_sigtramp_rt64() which confused glibc's backtrace logic, and also changed the semantics of that symbol, which was arguably an ABI break. - A fix for a stack overwrite in our VSX instruction emulation. - A couple of fixes for the Makefile logic in the new C VDSO. Thanks to Masahiro Yamada, Naveen N. Rao, Raoni Fassina Firmino, and Ravi Bangoria. * tag 'powerpc-5.11-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64/signal: Fix regression in __kernel_sigtramp_rt64() semantics powerpc/vdso64: remove meaningless vgettimeofday.o build rule powerpc/vdso: fix unnecessary rebuilds of vgettimeofday.o powerpc/sstep: Fix array out of bound warning
2021-02-07Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds7-78/+77
Pull ARM fixes from Russell King: - Fix latent bug with DC21285 (Footbridge PCI bridge) configuration accessors that affects GCC >= 4.9.2 - Fix misplaced tegra_uart_config in decompressor - Ensure signal page contents are initialised - Fix kexec oops * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: kexec: fix oops after TLB are invalidated ARM: ensure the signal page contains defined contents ARM: 9043/1: tegra: Fix misplaced tegra_uart_config in decompressor ARM: footbridge: fix dc21285 PCI configuration accessors
2021-02-06x86/efi: Remove EFI PGD build time checksBorislav Petkov1-19/+0
With CONFIG_X86_5LEVEL, CONFIG_UBSAN and CONFIG_UBSAN_UNSIGNED_OVERFLOW enabled, clang fails the build with x86_64-linux-ld: arch/x86/platform/efi/efi_64.o: in function `efi_sync_low_kernel_mappings': efi_64.c:(.text+0x22c): undefined reference to `__compiletime_assert_354' which happens due to -fsanitize=unsigned-integer-overflow being enabled: -fsanitize=unsigned-integer-overflow: Unsigned integer overflow, where the result of an unsigned integer computation cannot be represented in its type. Unlike signed integer overflow, this is not undefined behavior, but it is often unintentional. This sanitizer does not check for lossy implicit conversions performed before such a computation (see -fsanitize=implicit-conversion). and that fires when the (intentional) EFI_VA_START/END defines overflow an unsigned long, leading to the assertion expressions not getting optimized away (on GCC they do)... However, those checks are superfluous: the runtime services mapping code already makes sure the ranges don't overshoot EFI_VA_END as the EFI mapping range is hardcoded. On each runtime services call, it is switched to the EFI-specific PGD and even if mappings manage to escape that last PGD, this won't remain unnoticed for long. So rip them out. See https://github.com/ClangBuiltLinux/linux/issues/256 for more info. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Link: http://lkml.kernel.org/r/20210107223424.4135538-1-arnd@kernel.org
2021-02-06entry: Ensure trap after single-step on system call returnGabriel Krisman Bertazi2-4/+8
Commit 299155244770 ("entry: Drop usage of TIF flags in the generic syscall code") introduced a bug on architectures using the generic syscall entry code, in which processes stopped by PTRACE_SYSCALL do not trap on syscall return after receiving a TIF_SINGLESTEP. The reason is that the meaning of TIF_SINGLESTEP flag is overloaded to cause the trap after a system call is executed, but since the above commit, the syscall call handler only checks for the SYSCALL_WORK flags on the exit work. Split the meaning of TIF_SINGLESTEP such that it only means single-step mode, and create a new type of SYSCALL_WORK to request a trap immediately after a syscall in single-step mode. In the current implementation, the SYSCALL_WORK flag shadows the TIF_SINGLESTEP flag for simplicity. Update x86 to flip this bit when a tracer enables single stepping. Fixes: 299155244770 ("entry: Drop usage of TIF flags in the generic syscall code") Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/87h7mtc9pr.fsf_-_@collabora.com
2021-02-05x86/debug: Prevent data breakpoints on cpu_dr7Lai Jiangshan1-0/+8
local_db_save() is called at the start of exc_debug_kernel(), reads DR7 and disables breakpoints to prevent recursion. When running in a guest (X86_FEATURE_HYPERVISOR), local_db_save() reads the per-cpu variable cpu_dr7 to check whether a breakpoint is active or not before it accesses DR7. A data breakpoint on cpu_dr7 therefore results in infinite #DB recursion. Disallow data breakpoints on cpu_dr7 to prevent that. Fixes: 84b6a3491567a("x86/entry: Optimize local_db_save() for virt") Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210204152708.21308-2-jiangshanlai@gmail.com
2021-02-05x86/debug: Prevent data breakpoints on __per_cpu_offsetLai Jiangshan1-0/+14
When FSGSBASE is enabled, paranoid_entry() fetches the per-CPU GSBASE value via __per_cpu_offset or pcpu_unit_offsets. When a data breakpoint is set on __per_cpu_offset[cpu] (read-write operation), the specific CPU will be stuck in an infinite #DB loop. RCU will try to send an NMI to the specific CPU, but it is not working either since NMI also relies on paranoid_entry(). Which means it's undebuggable. Fixes: eaad981291ee3("x86/entry/64: Introduce the FIND_PERCPU_BASE macro") Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210204152708.21308-1-jiangshanlai@gmail.com
2021-02-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds12-47/+72
Pull KVM fixes from Paolo Bonzini: "x86 has lots of small bugfixes, mostly one liners. It's quite late in 5.11-rc but none of them are related to this merge window; it's just bugs coming in at the wrong time. Of note among the others is "KVM: x86: Allow guests to see MSR_IA32_TSX_CTRL even if tsx=off" that fixes a live migration failure seen on distros that hadn't switched to tsx=off right away. ARM: - Avoid clobbering extra registers on initialisation" [ Sean Christopherson notes that commit 943dea8af21b ("KVM: x86: Update emulator context mode if SYSENTER xfers to 64-bit mode") should have had authorship credited to Jonny Barker, not to him. - Linus ] * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: Set so called 'reserved CR3 bits in LM mask' at vCPU reset KVM: x86/mmu: Fix TDP MMU zap collapsible SPTEs KVM: x86: cleanup CR3 reserved bits checks KVM: SVM: Treat SVM as unsupported when running as an SEV guest KVM: x86: Update emulator context mode if SYSENTER xfers to 64-bit mode KVM: x86: Supplement __cr4_reserved_bits() with X86_FEATURE_PCID check KVM/x86: assign hva with the right value to vm_munmap the pages KVM: x86: Allow guests to see MSR_IA32_TSX_CTRL even if tsx=off Fix unsynchronized access to sev members through svm_register_enc_region KVM: Documentation: Fix documentation for nested. KVM: x86: fix CPUID entries returned by KVM_GET_CPUID2 ioctl KVM: arm64: Don't clobber x4 in __do_hyp_init
2021-02-05ARM: kexec: fix oops after TLB are invalidatedRussell King4-39/+36
Giancarlo Ferrari reports the following oops while trying to use kexec: Unable to handle kernel paging request at virtual address 80112f38 pgd = fd7ef03e [80112f38] *pgd=0001141e(bad) Internal error: Oops: 80d [#1] PREEMPT SMP ARM ... This is caused by machine_kexec() trying to set the kernel text to be read/write, so it can poke values into the relocation code before copying it - and an interrupt occuring which changes the page tables. The subsequent writes then hit read-only sections that trigger a data abort resulting in the above oops. Fix this by copying the relocation code, and then writing the variables into the destination, thereby avoiding the need to make the kernel text read/write. Reported-by: Giancarlo Ferrari <giancarlo.ferrari89@gmail.com> Tested-by: Giancarlo Ferrari <giancarlo.ferrari89@gmail.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-02-05ARM: ensure the signal page contains defined contentsRussell King1-6/+8
Ensure that the signal page contains our poison instruction to increase the protection against ROP attacks and also contains well defined contents. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-02-04x86/apic: Add extra serialization for non-serializing MSRsDave Hansen5-15/+32
Jan Kiszka reported that the x2apic_wrmsr_fence() function uses a plain MFENCE while the Intel SDM (10.12.3 MSR Access in x2APIC Mode) calls for MFENCE; LFENCE. Short summary: we have special MSRs that have weaker ordering than all the rest. Add fencing consistent with current SDM recommendations. This is not known to cause any issues in practice, only in theory. Longer story below: The reason the kernel uses a different semantic is that the SDM changed (roughly in late 2017). The SDM changed because folks at Intel were auditing all of the recommended fences in the SDM and realized that the x2apic fences were insufficient. Why was the pain MFENCE judged insufficient? WRMSR itself is normally a serializing instruction. No fences are needed because the instruction itself serializes everything. But, there are explicit exceptions for this serializing behavior written into the WRMSR instruction documentation for two classes of MSRs: IA32_TSC_DEADLINE and the X2APIC MSRs. Back to x2apic: WRMSR is *not* serializing in this specific case. But why is MFENCE insufficient? MFENCE makes writes visible, but only affects load/store instructions. WRMSR is unfortunately not a load/store instruction and is unaffected by MFENCE. This means that a non-serializing WRMSR could be reordered by the CPU to execute before the writes made visible by the MFENCE have even occurred in the first place. This means that an x2apic IPI could theoretically be triggered before there is any (visible) data to process. Does this affect anything in practice? I honestly don't know. It seems quite possible that by the time an interrupt gets to consume the (not yet) MFENCE'd data, it has become visible, mostly by accident. To be safe, add the SDM-recommended fences for all x2apic WRMSRs. This also leaves open the question of the _other_ weakly-ordered WRMSR: MSR_IA32_TSC_DEADLINE. While it has the same ordering architecture as the x2APIC MSRs, it seems substantially less likely to be a problem in practice. While writes to the in-memory Local Vector Table (LVT) might theoretically be reordered with respect to a weakly-ordered WRMSR like TSC_DEADLINE, the SDM has this to say: In x2APIC mode, the WRMSR instruction is used to write to the LVT entry. The processor ensures the ordering of this write and any subsequent WRMSR to the deadline; no fencing is required. But, that might still leave xAPIC exposed. The safest thing to do for now is to add the extra, recommended LFENCE. [ bp: Massage commit message, fix typos, drop accidentally added newline to tools/arch/x86/include/asm/barrier.h. ] Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20200305174708.F77040DD@viggo.jf.intel.com
2021-02-04Revert "x86/setup: don't remove E820_TYPE_RAM for pfn 0"Mike Rapoport1-9/+11
This reverts commit bde9cfa3afe4324ec251e4af80ebf9b7afaf7afe. Changing the first memory page type from E820_TYPE_RESERVED to E820_TYPE_RAM makes it a part of "System RAM" resource rather than a reserved resource and this in turn causes devmem_is_allowed() to treat is as area that can be accessed but it is filled with zeroes instead of the actual data as previously. The change in /dev/mem output causes lilo to fail as was reported at slakware users forum, and probably other legacy applications will experience similar problems. Link: https://www.linuxquestions.org/questions/slackware-14/slackware-current-lilo-vesa-warnings-after-recent-updates-4175689617/#post6214439 Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-04KVM: x86: Set so called 'reserved CR3 bits in LM mask' at vCPU resetSean Christopherson1-0/+1
Set cr3_lm_rsvd_bits, which is effectively an invalid GPA mask, at vCPU reset. The reserved bits check needs to be done even if userspace never configures the guest's CPUID model. Cc: stable@vger.kernel.org Fixes: 0107973a80ad ("KVM: x86: Introduce cr3_lm_rsvd_bits in kvm_vcpu_arch") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210204000117.3303214-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-04KVM: x86/mmu: Fix TDP MMU zap collapsible SPTEsBen Gardon1-3/+3
There is a bug in the TDP MMU function to zap SPTEs which could be replaced with a larger mapping which prevents the function from doing anything. Fix this by correctly zapping the last level SPTEs. Cc: stable@vger.kernel.org Fixes: 14881998566d ("kvm: x86/mmu: Support disabling dirty logging for the tdp MMU") Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20210202185734.1680553-11-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-03Merge tag 'for-linus-5.11-rc7' of ↵Linus Torvalds14-99/+84
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML fixes from Richard Weinberger: - Make sure to set a default console, otherwise ttynull is selected - Revert initial ARCH_HAS_SET_MEMORY support, this needs more work - Fix a regression due to ubd refactoring - Various small fixes * tag 'for-linus-5.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: um: time: fix initialization in time-travel mode um: fix os_idle_sleep() to not hang Revert "um: support some of ARCH_HAS_SET_MEMORY" Revert "um: allocate a guard page to helper threads" um: virtio: free vu_dev only with the contained struct device um: kmsg_dumper: always dump when not tty console um: stdio_console: Make preferred console um: return error from ioremap() um: ubd: fix command line handling of ubd
2021-02-03Merge tag 'arm64-fixes' of ↵Linus Torvalds2-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Catalin Marinas: "Fix the arm64 linear map range detection for tagged addresses and replace the bitwise operations with subtract (virt_addr_valid(), __is_lm_address(), __lm_to_phys())" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: Use simpler arithmetics for the linear map macros arm64: Do not pass tagged addresses to __is_lm_address()
2021-02-03Merge tag 'arm-soc-fixes-v5.11-3' of ↵Linus Torvalds23-61/+65
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull ARM SoC fixes from Arnd Bergmann: "The code fixes in this round are all for the Texas Instruments OMAP platform, addressing several regressions related to the ti-sysc interconnect changes that was merged in linux-5.11 and one recently introduced RCU usage warning. Tero Kristo updates his maintainer file entries as he is changing to a new employer. The other changes are for devicetree files across eight different platforms: TI OMAP: - multiple gpio related one-line fixes Allwinner/sunxi: - ARM: dts: sun7i: a20: bananapro: Fix ethernet phy-mode - soc: sunxi: mbus: Remove DE2 display engine compatibles NXP lpc32xx: - ARM: dts: lpc32xx: Revert set default clock rate of HCLK PLL STMicroelectronics stm32 - multiple minor fixes for DHCOM/DHCOR boards NXP Layerscape: - Fix DCFG address range on LS1046A SoC Amlogic meson: - fix reboot issue on odroid C4 - revert an ethernet change that caused a regression - meson-g12: Set FL-adj property value Rockchip: - multiple minor fixes on 64-bit rockchip machines Qualcomm: - Regression fixes for Lenovo Yoga touchpad and for interconnect configuration - Boot fixes for 'LPASS' clock configuration on two machines" * tag 'arm-soc-fixes-v5.11-3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (31 commits) ARM: dts: lpc32xx: Revert set default clock rate of HCLK PLL ARM: dts: sun7i: a20: bananapro: Fix ethernet phy-mode arm64: dts: ls1046a: fix dcfg address range soc: sunxi: mbus: Remove DE2 display engine compatibles arm64: dts: meson: switch TFLASH_VDD_EN pin to open drain on Odroid-C4 Revert "arm64: dts: amlogic: add missing ethernet reset ID" arm64: dts: rockchip: Disable display for NanoPi R2S ARM: dts: omap4-droid4: Fix lost keypad slide interrupts for droid4 arm64: dts: rockchip: remove interrupt-names property from rk3399 vdec node drivers: bus: simple-pm-bus: Fix compatibility with simple-bus for auxdata ARM: OMAP2+: Fix booting for am335x after moving to simple-pm-bus ARM: OMAP2+: Fix suspcious RCU usage splats for omap_enter_idle_coupled ARM: dts: stm32: Fix GPIO hog flags on DHCOM DRC02 ARM: dts: stm32: Fix GPIO hog flags on DHCOM PicoITX ARM: dts: stm32: Fix GPIO hog names on DHCOM ARM: dts: stm32: Disable optional TSC2004 on DRC02 board ARM: dts: stm32: Disable WP on DHCOM uSD slot ARM: dts: stm32: Connect card-detect signal on DHCOM ARM: dts: stm32: Fix polarity of the DH DRC02 uSD card detect arm64: dts: qcom: sdm845: Reserve LPASS clocks in gcc ...
2021-02-03Merge tag 'sunxi-fixes-for-5.11-2' of ↵Arnd Bergmann1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into arm/fixes One fix for a phy-mode ethernet issue, and one to fix the display output on SoCs with the Display Engine 2 * tag 'sunxi-fixes-for-5.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux: ARM: dts: sun7i: a20: bananapro: Fix ethernet phy-mode soc: sunxi: mbus: Remove DE2 display engine compatibles Link: https://lore.kernel.org/r/f8298059-f9ca-43b4-9e29-35bc0e0c9b15.lettre@localhost Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2021-02-03ARM: dts: lpc32xx: Revert set default clock rate of HCLK PLLAlexandre Belloni1-3/+0
This reverts commit c17e9377aa81664d94b4f2102559fcf2a01ec8e7. The lpc32xx clock driver is not able to actually change the PLL rate as this would require reparenting ARM_CLK, DDRAM_CLK, PERIPH_CLK to SYSCLK, then stop the PLL, update the register, restart the PLL and wait for the PLL to lock and finally reparent ARM_CLK, DDRAM_CLK, PERIPH_CLK to HCLK PLL. Currently, the HCLK driver simply updates the registers but this has no real effect and all the clock rate calculation end up being wrong. This is especially annoying for the peripheral (e.g. UARTs, I2C, SPI). Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://lore.kernel.org/r/20210203090320.GA3760268@piout.net' Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2021-02-03ARM: dts: sun7i: a20: bananapro: Fix ethernet phy-modeHermann Lauer1-1/+1
BPi Pro needs TX and RX delay for Gbit to work reliable and avoid high packet loss rates. The realtek phy driver overrides the settings of the pull ups for the delays, so fix this for BananaPro. Fix the phy-mode description to correctly reflect this so that the implementation doesn't reconfigure the delays incorrectly. This happened with commit bbc4d71d6354 ("net: phy: realtek: fix rtl8211e rx/tx delay config"). Fixes: 10662a33dcd9 ("ARM: dts: sun7i: Add dts file for Bananapro board") Signed-off-by: Hermann Lauer <Hermann.Lauer@uni-heidelberg.de> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Link: https://lore.kernel.org/r/20210128111842.GA11919@lemon.iwr.uni-heidelberg.de
2021-02-03KVM: x86: cleanup CR3 reserved bits checksPaolo Bonzini3-13/+5
If not in long mode, the low bits of CR3 are reserved but not enforced to be zero, so remove those checks. If in long mode, however, the MBZ bits extend down to the highest physical address bit of the guest, excluding the encryption bit. Make the checks consistent with the above, and match them between nested_vmcb_checks and KVM_SET_SREGS. Cc: stable@vger.kernel.org Fixes: 761e41693465 ("KVM: nSVM: Check that MBZ bits in CR3 and CR4 are not set on vmrun of nested guests") Fixes: a780a3ea6282 ("KVM: X86: Fix reserved bits check for MOV to CR3") Reviewed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-03KVM: SVM: Treat SVM as unsupported when running as an SEV guestSean Christopherson2-0/+6
Don't let KVM load when running as an SEV guest, regardless of what CPUID says. Memory is encrypted with a key that is not accessible to the host (L0), thus it's impossible for L0 to emulate SVM, e.g. it'll see garbage when reading the VMCB. Technically, KVM could decrypt all memory that needs to be accessible to the L0 and use shadow paging so that L0 does not need to shadow NPT, but exposing such information to L0 largely defeats the purpose of running as an SEV guest. This can always be revisited if someone comes up with a use case for running VMs inside SEV guests. Note, VMLOAD, VMRUN, etc... will also #GP on GPAs with C-bit set, i.e. KVM is doomed even if the SEV guest is debuggable and the hypervisor is willing to decrypt the VMCB. This may or may not be fixed on CPUs that have the SVME_ADDR_CHK fix. Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210202212017.2486595-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-03RISC-V: Define MAXPHYSMEM_1GB only for RV32Atish Patra1-0/+2
MAXPHYSMEM_1GB option was added for RV32 because RV32 only supports 1GB of maximum physical memory. This lead to few compilation errors reported by kernel test robot which created the following configuration combination which are not useful but can be configured. 1. MAXPHYSMEM_1GB & RV64 2, MAXPHYSMEM_2GB & RV32 Fix this by restricting MAXPHYSMEM_1GB for RV32 and MAXPHYSMEM_2GB only for RV64. Fixes: e557793799c5 ("RISC-V: Fix maximum allowed phsyical memory for RV32") Cc: stable@vger.kernel.org Reported-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-03riscv: Align on L1_CACHE_BYTES when STRICT_KERNEL_RWXSebastien Van Cauwenberghe1-3/+3
Allows the sections to be aligned on smaller boundaries and therefore results in a smaller kernel image size. Signed-off-by: Sebastien Van Cauwenberghe <svancau@gmail.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-03RISC-V: Fix .init section permission updateAtish Patra1-1/+3
.init section permission should only updated to non-execute if STRICT_KERNEL_RWX is enabled. Otherwise, this will lead to a kernel hang. Fixes: 19a00869028f ("RISC-V: Protect all kernel sections including init early") Cc: stable@vger.kernel.org Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-02-03riscv: virt_addr_valid must check the address belongs to linear mappingAlexandre Ghiti1-1/+4
virt_addr_valid macro checks that a virtual address is valid, ie that the address belongs to the linear mapping and that the corresponding physical page exists. Add the missing check that ensures the virtual address belongs to the linear mapping, otherwise __virt_to_phys, when compiled with CONFIG_DEBUG_VIRTUAL enabled, raises a WARN that is interpreted as a kernel bug by syzbot. Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>