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* x86/entry: Move nmi entry/exit into common codeThomas Gleixner2020-11-045-49/+13
| | | | | | | | | | | | | | | | | Lockdep state handling on NMI enter and exit is nothing specific to X86. It's not any different on other architectures. Also the extra state type is not necessary, irqentry_state_t can carry the necessary information as well. Move it to common code and extend irqentry_state_t to carry lockdep state. [ Ira: Make exit_rcu and lockdep a union as they are mutually exclusive between the IRQ and NMI exceptions, and add kernel documentation for struct irqentry_state_t ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20201102205320.1458656-7-ira.weiny@intel.com
* Merge branch 'core/urgent' into core/entryThomas Gleixner2020-11-04333-12851/+18420
|\ | | | | | | Pick up the entry fix before further modifications.
| * Merge tag 'x86-urgent-2020-11-01' of ↵Linus Torvalds2020-11-011-13/+30
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "Three fixes all related to #DB: - Handle the BTF bit correctly so it doesn't get lost due to a kernel #DB - Only clear and set the virtual DR6 value used by ptrace on user space triggered #DB. A kernel #DB must leave it alone to ensure data consistency for ptrace. - Make the bitmasking of the virtual DR6 storage correct so it does not lose DR_STEP" * tag 'x86-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/debug: Fix DR_STEP vs ptrace_get_debugreg(6) x86/debug: Only clear/set ->virtual_dr6 for userspace #DB x86/debug: Fix BTF handling
| | * x86/debug: Fix DR_STEP vs ptrace_get_debugreg(6)Peter Zijlstra2020-10-271-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit d53d9bc0cf78 ("x86/debug: Change thread.debugreg6 to thread.virtual_dr6") changed the semantics of the variable from random collection of bits, to exactly only those bits that ptrace() needs. Unfortunately this lost DR_STEP for PTRACE_{BLOCK,SINGLE}STEP. Furthermore, it turns out that userspace expects DR_STEP to be unconditionally available, even for manual TF usage outside of PTRACE_{BLOCK,SINGLE}_STEP. Fixes: d53d9bc0cf78 ("x86/debug: Change thread.debugreg6 to thread.virtual_dr6") Reported-by: Kyle Huey <me@kylehuey.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/20201027183330.GM2628@hirez.programming.kicks-ass.net
| | * x86/debug: Only clear/set ->virtual_dr6 for userspace #DBPeter Zijlstra2020-10-271-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ->virtual_dr6 is the value used by ptrace_{get,set}_debugreg(6). A kernel #DB clearing it could mean spurious malfunction of ptrace() expectations. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/20201027093608.028952500@infradead.org
| | * x86/debug: Fix BTF handlingPeter Zijlstra2020-10-271-7/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The SDM states that #DB clears DEBUGCTLMSR_BTF, this means that when the bit is set for userspace (TIF_BLOCKSTEP) and a kernel #DB happens first, the BTF bit meant for userspace execution is lost. Have the kernel #DB handler restore the BTF bit when it was requested for userspace. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/20201027093607.956147736@infradead.org
| * | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2020-11-018-32/+31
| |\ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm fixes from Paolo Bonzini: "ARM: - selftest fix - force PTE mapping on device pages provided via VFIO - fix detection of cacheable mapping at S2 - fallback to PMD/PTE mappings for composite huge pages - fix accounting of Stage-2 PGD allocation - fix AArch32 handling of some of the debug registers - simplify host HYP entry - fix stray pointer conversion on nVHE TLB invalidation - fix initialization of the nVHE code - simplify handling of capabilities exposed to HYP - nuke VCPUs caught using a forbidden AArch32 EL0 x86: - new nested virtualization selftest - miscellaneous fixes - make W=1 fixes - reserve new CPUID bit in the KVM leaves" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: vmx: remove unused variable KVM: selftests: Don't require THP to run tests KVM: VMX: eVMCS: make evmcs_sanitize_exec_ctrls() work again KVM: selftests: test behavior of unmapped L2 APIC-access address KVM: x86: Fix NULL dereference at kvm_msr_ignored_check() KVM: x86: replace static const variables with macros KVM: arm64: Handle Asymmetric AArch32 systems arm64: cpufeature: upgrade hyp caps to final arm64: cpufeature: reorder cpus_have_{const, final}_cap() KVM: arm64: Factor out is_{vhe,nvhe}_hyp_code() KVM: arm64: Force PTE mapping on fault resulting in a device mapping KVM: arm64: Use fallback mapping sizes for contiguous huge page sizes KVM: arm64: Fix masks in stage2_pte_cacheable() KVM: arm64: Fix AArch32 handling of DBGD{CCINT,SCRext} and DBGVCR KVM: arm64: Allocate stage-2 pgd pages with GFP_KERNEL_ACCOUNT KVM: arm64: Drop useless PAN setting on host EL1 to EL2 transition KVM: arm64: Remove leftover kern_hyp_va() in nVHE TLB invalidation KVM: arm64: Don't corrupt tpidr_el2 on failed HVC call x86/kvm: Reserve KVM_FEATURE_MSI_EXT_DEST_ID
| | * KVM: vmx: remove unused variablePaolo Bonzini2020-10-311-2/+0
| | | | | | | | | | | | | | | Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * KVM: VMX: eVMCS: make evmcs_sanitize_exec_ctrls() work againVitaly Kuznetsov2020-10-313-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was noticed that evmcs_sanitize_exec_ctrls() is not being executed nowadays despite the code checking 'enable_evmcs' static key looking correct. Turns out, static key magic doesn't work in '__init' section (and it is unclear when things changed) but setup_vmcs_config() is called only once per CPU so we don't really need it to. Switch to checking 'enlightened_vmcs' instead, it is supposed to be in sync with 'enable_evmcs'. Opportunistically make evmcs_sanitize_exec_ctrls '__init' and drop unneeded extra newline from it. Reported-by: Yang Weijiang <weijiang.yang@intel.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20201014143346.2430936-1-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * KVM: x86: Fix NULL dereference at kvm_msr_ignored_check()Takashi Iwai2020-10-301-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The newly introduced kvm_msr_ignored_check() tries to print error or debug messages via vcpu_*() macros, but those may cause Oops when NULL vcpu is passed for KVM_GET_MSRS ioctl. Fix it by replacing the print calls with kvm_*() macros. (Note that this will leave vcpu argument completely unused in the function, but I didn't touch it to make the fix as small as possible. A clean up may be applied later.) Fixes: 12bc2132b15e ("KVM: X86: Do the same ignore_msrs check for feature msrs") BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1178280 Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de> Message-Id: <20201030151414.20165-1-tiwai@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * KVM: x86: replace static const variables with macrosPaolo Bonzini2020-10-303-21/+21
| | | | | | | | | | | | | | | | | | | | | | | | Even though the compiler is able to replace static const variables with their value, it will warn about them being unused when Linux is built with W=1. Use good old macros instead, this is not C++. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * x86/kvm: Reserve KVM_FEATURE_MSI_EXT_DEST_IDDavid Woodhouse2020-10-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No functional change; just reserve the feature bit for now so that VMMs can start to implement it. This will allow the host to indicate that MSI emulation supports 15-bit destination IDs, allowing up to 32768 CPUs without interrupt remapping. cf. https://patchwork.kernel.org/patch/11816693/ for qemu Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <4cd59bed05f4b7410d3d1ffd1e997ab53683874d.camel@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | Merge tag 'x86-urgent-2020-10-27' of ↵Linus Torvalds2020-10-274-14/+17
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A couple of x86 fixes which missed rc1 due to my stupidity: - Drop lazy TLB mode before switching to the temporary address space for text patching. text_poke() switches to the temporary mm which clears the lazy mode and restores the original mm afterwards. Due to clearing lazy mode this might restore a already dead mm if exit_mmap() runs in parallel on another CPU. - Document the x32 syscall design fail vs. syscall numbers 512-547 properly. - Fix the ORC unwinder to handle the inactive task frame correctly. This was unearthed due to the slightly different code generation of gcc-10. - Use an up to date screen_info for the boot params of kexec instead of the possibly stale and invalid version which happened to be valid when the kexec kernel was loaded" * tag 'x86-urgent-2020-10-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/alternative: Don't call text_poke() in lazy TLB mode x86/syscalls: Document the fact that syscalls 512-547 are a legacy mistake x86/unwind/orc: Fix inactive tasks with stack pointer in %sp on GCC 10 compiled kernels hyperv_fb: Update screen_info after removing old framebuffer x86/kexec: Use up-to-dated screen_info copy to fill boot params
| | * | x86/alternative: Don't call text_poke() in lazy TLB modeJuergen Gross2020-10-221-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When running in lazy TLB mode the currently active page tables might be the ones of a previous process, e.g. when running a kernel thread. This can be problematic in case kernel code is being modified via text_poke() in a kernel thread, and on another processor exit_mmap() is active for the process which was running on the first cpu before the kernel thread. As text_poke() is using a temporary address space and the former address space (obtained via cpu_tlbstate.loaded_mm) is restored afterwards, there is a race possible in case the cpu on which exit_mmap() is running wants to make sure there are no stale references to that address space on any cpu active (this e.g. is required when running as a Xen PV guest, where this problem has been observed and analyzed). In order to avoid that, drop off TLB lazy mode before switching to the temporary address space. Fixes: cefa929c034eb5d ("x86/mm: Introduce temporary mm structs") Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20201009144225.12019-1-jgross@suse.com
| | * | x86/syscalls: Document the fact that syscalls 512-547 are a legacy mistakeAndy Lutomirski2020-10-141-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since this commit: 6365b842aae4 ("x86/syscalls: Split the x32 syscalls into their own table") there is no need for special x32-specific syscall numbers. I forgot to update the comments in syscall_64.tbl. Add comments to make it clear to future contributors that this range is a legacy wart. Reported-by: Jessica Clarke <jrtc27@jrtc27.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/6c56fb4ddd18fc60a238eb4d867e4b3d97c6351e.1602471055.git.luto@kernel.org
| | * | x86/unwind/orc: Fix inactive tasks with stack pointer in %sp on GCC 10 ↵Jiri Slaby2020-10-141-8/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | compiled kernels GCC 10 optimizes the scheduler code differently than its predecessors. When CONFIG_DEBUG_SECTION_MISMATCH=y, the Makefile forces GCC not to inline some functions (-fno-inline-functions-called-once). Before GCC 10, "no-inlined" __schedule() starts with the usual prologue: push %bp mov %sp, %bp So the ORC unwinder simply picks stack pointer from %bp and unwinds from __schedule() just perfectly: $ cat /proc/1/stack [<0>] ep_poll+0x3e9/0x450 [<0>] do_epoll_wait+0xaa/0xc0 [<0>] __x64_sys_epoll_wait+0x1a/0x20 [<0>] do_syscall_64+0x33/0x40 [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 But now, with GCC 10, there is no %bp prologue in __schedule(): $ cat /proc/1/stack <nothing> The ORC entry of the point in __schedule() is: sp:sp+88 bp:last_sp-48 type:call end:0 In this case, nobody subtracts sizeof "struct inactive_task_frame" in __unwind_start(). The struct is put on the stack by __switch_to_asm() and only then __switch_to_asm() stores %sp to task->thread.sp. But we start unwinding from a point in __schedule() (stored in frame->ret_addr by 'call') and not in __switch_to_asm(). So for these example values in __unwind_start(): sp=ffff94b50001fdc8 bp=ffff8e1f41d29340 ip=__schedule+0x1f0 The stack is: ffff94b50001fdc8: ffff8e1f41578000 # struct inactive_task_frame ffff94b50001fdd0: 0000000000000000 ffff94b50001fdd8: ffff8e1f41d29340 ffff94b50001fde0: ffff8e1f41611d40 # ... ffff94b50001fde8: ffffffff93c41920 # bx ffff94b50001fdf0: ffff8e1f41d29340 # bp ffff94b50001fdf8: ffffffff9376cad0 # ret_addr (and end of the struct) 0xffffffff9376cad0 is __schedule+0x1f0 (after the call to __switch_to_asm). Now follow those 88 bytes from the ORC entry (sp+88). The entry is correct, __schedule() really pushes 48 bytes (8*7) + 32 bytes via subq to store some local values (like 4U below). So to unwind, look at the offset 88-sizeof(long) = 0x50 from here: ffff94b50001fe00: ffff8e1f41578618 ffff94b50001fe08: 00000cc000000255 ffff94b50001fe10: 0000000500000004 ffff94b50001fe18: 7793fab6956b2d00 # NOTE (see below) ffff94b50001fe20: ffff8e1f41578000 ffff94b50001fe28: ffff8e1f41578000 ffff94b50001fe30: ffff8e1f41578000 ffff94b50001fe38: ffff8e1f41578000 ffff94b50001fe40: ffff94b50001fed8 ffff94b50001fe48: ffff8e1f41577ff0 ffff94b50001fe50: ffffffff9376cf12 Here ^^^^^^^^^^^^^^^^ is the correct ret addr from __schedule(). It translates to schedule+0x42 (insn after a call to __schedule()). BUT, unwind_next_frame() tries to take the address starting from 0xffff94b50001fdc8. That is exactly from thread.sp+88-sizeof(long) = 0xffff94b50001fdc8+88-8 = 0xffff94b50001fe18, which is garbage marked as NOTE above. So this quits the unwinding as 7793fab6956b2d00 is obviously not a kernel address. There was a fix to skip 'struct inactive_task_frame' in unwind_get_return_address_ptr in the following commit: 187b96db5ca7 ("x86/unwind/orc: Fix unwind_get_return_address_ptr() for inactive tasks") But we need to skip the struct already in the unwinder proper. So subtract the size (increase the stack pointer) of the structure in __unwind_start() directly. This allows for removal of the code added by commit 187b96db5ca7 completely, as the address is now at '(unsigned long *)state->sp - 1', the same as in the generic case. [ mingo: Cleaned up the changelog a bit, for better readability. ] Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Bug: https://bugzilla.suse.com/show_bug.cgi?id=1176907 Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20201014053051.24199-1-jslaby@suse.cz
| | * | x86/kexec: Use up-to-dated screen_info copy to fill boot paramsKairui Song2020-10-141-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kexec_file_load() currently reuses the old boot_params.screen_info, but if drivers have change the hardware state, boot_param.screen_info could contain invalid info. For example, the video type might be no longer VGA, or the frame buffer address might be changed. If the kexec kernel keeps using the old screen_info, kexec'ed kernel may attempt to write to an invalid framebuffer memory region. There are two screen_info instances globally available, boot_params.screen_info and screen_info. Later one is a copy, and is updated by drivers. So let kexec_file_load use the updated copy. [ mingo: Tidied up the changelog. ] Signed-off-by: Kairui Song <kasong@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20201014092429.1415040-2-kasong@redhat.com
| * | | arch/um: partially revert the conversion to __section() macroLinus Torvalds2020-10-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A couple of um files ended up not including the header file that defines the __section() macro, and the simplest fix is to just revert the change for those files. Fixes: 33def8498fdd treewide: Convert macro and uses of __section(foo) to __section("foo") Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Joe Perches <joe@perches.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | Merge branch 'linus' of ↵Linus Torvalds2020-10-261-0/+1
| |\ \ \ | | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto fix from Herbert Xu: "This fixes a regression in x86/poly1305" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: x86/poly1305 - add back a needed assignment
| | * | crypto: x86/poly1305 - add back a needed assignmentEric Biggers2020-10-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | One of the assignments that was removed by commit 4a0c1de64bf9 ("crypto: x86/poly1305 - Remove assignments with no effect") is actually needed, since it affects the return value. This fixes the following crypto self-test failure: alg: shash: poly1305-simd test failed (wrong result) on test vector 2, cfg="init+update+final aligned buffer" Fixes: 4a0c1de64bf9 ("crypto: x86/poly1305 - Remove assignments with no effect") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
| * | | treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches2020-10-2518-29/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | Merge tag 'for-linus-5.10b-rc1c-tag' of ↵Linus Torvalds2020-10-252-8/+13
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull more xen updates from Juergen Gross: - a series for the Xen pv block drivers adding module parameters for better control of resource usge - a cleanup series for the Xen event driver * tag 'for-linus-5.10b-rc1c-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: Documentation: add xen.fifo_events kernel parameter description xen/events: unmask a fifo event channel only if it was masked xen/events: only register debug interrupt for 2-level events xen/events: make struct irq_info private to events_base.c xen: remove no longer used functions xen-blkfront: Apply changed parameter name to the document xen-blkfront: add a parameter for disabling of persistent grants xen-blkback: add a parameter for disabling of persistent grants
| | * | | xen/events: only register debug interrupt for 2-level eventsJuergen Gross2020-10-232-8/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xen_debug_interrupt() is specific to 2-level event handling. So don't register it with fifo event handling being active. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Link: https://lore.kernel.org/r/20201022094907.28560-4-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
| * | | | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2020-10-245-9/+6
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM fixes from Paolo Bonzini: "Two fixes for this merge window, and an unrelated bugfix for a host hang" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: ioapic: break infinite recursion on lazy EOI KVM: vmx: rename pi_init to avoid conflict with paride KVM: x86/mmu: Avoid modulo operator on 64-bit value to fix i386 build
| | * | | | KVM: ioapic: break infinite recursion on lazy EOIVitaly Kuznetsov2020-10-241-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During shutdown the IOAPIC trigger mode is reset to edge triggered while the vfio-pci INTx is still registered with a resampler. This allows us to get into an infinite loop: ioapic_set_irq -> ioapic_lazy_update_eoi -> kvm_ioapic_update_eoi_one -> kvm_notify_acked_irq -> kvm_notify_acked_gsi -> (via irq_acked fn ptr) irqfd_resampler_ack -> kvm_set_irq -> (via set fn ptr) kvm_set_ioapic_irq -> kvm_ioapic_set_irq -> ioapic_set_irq Commit 8be8f932e3db ("kvm: ioapic: Restrict lazy EOI update to edge-triggered interrupts", 2020-05-04) acknowledges that this recursion loop exists and tries to avoid it at the call to ioapic_lazy_update_eoi, but at this point the scenario is already set, we have an edge interrupt with resampler on the same gsi. Fortunately, the only user of irq ack notifiers (in addition to resamplefd) is i8254 timer interrupt reinjection. These are edge-triggered, so in principle they would need the call to kvm_ioapic_update_eoi_one from ioapic_lazy_update_eoi, but they already disable AVIC(*), so they don't need the lazy EOI behavior. Therefore, remove the call to kvm_ioapic_update_eoi_one from ioapic_lazy_update_eoi. This fixes CVE-2020-27152. Note that this issue cannot happen with SR-IOV assigned devices because virtual functions do not have INTx, only MSI. Fixes: f458d039db7e ("kvm: ioapic: Lazy update IOAPIC EOI") Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | KVM: vmx: rename pi_init to avoid conflict with paridePaolo Bonzini2020-10-243-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | allyesconfig results in: ld: drivers/block/paride/paride.o: in function `pi_init': (.text+0x1340): multiple definition of `pi_init'; arch/x86/kvm/vmx/posted_intr.o:posted_intr.c:(.init.text+0x0): first defined here make: *** [Makefile:1164: vmlinux] Error 1 because commit: commit 8888cdd0996c2d51cd417f9a60a282c034f3fa28 Author: Xiaoyao Li <xiaoyao.li@intel.com> Date: Wed Sep 23 11:31:11 2020 -0700 KVM: VMX: Extract posted interrupt support to separate files added another pi_init(), though one already existed in the paride code. Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | KVM: x86/mmu: Avoid modulo operator on 64-bit value to fix i386 buildSean Christopherson2020-10-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace a modulo operator with the more common pattern for computing the gfn "offset" of a huge page to fix an i386 build error. arch/x86/kvm/mmu/tdp_mmu.c:212: undefined reference to `__umoddi3' In fact, almost all of tdp_mmu.c can be elided on 32-bit builds, but that is a much larger patch. Fixes: 2f2fad0897cb ("kvm: x86/mmu: Add functions to handle changed TDP SPTEs") Reported-by: Daniel Díaz <daniel.diaz@linaro.org> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20201024031150.9318-1-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | | Merge tag 'x86_seves_fixes_for_v5.10_rc1' of ↵Linus Torvalds2020-10-245-16/+40
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SEV-ES fixes from Borislav Petkov: "Three fixes to SEV-ES to correct setting up the new early pagetable on 5-level paging machines, to always map boot_params and the kernel cmdline, and disable stack protector for ../compressed/head{32,64}.c. (Arvind Sankar)" * tag 'x86_seves_fixes_for_v5.10_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot/64: Explicitly map boot_params and command line x86/head/64: Disable stack protection for head$(BITS).o x86/boot/64: Initialize 5-level paging variables earlier
| | * | | | | x86/boot/64: Explicitly map boot_params and command lineArvind Sankar2020-10-192-3/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits ca0e22d4f011 ("x86/boot/compressed/64: Always switch to own page table") 8570978ea030 ("x86/boot/compressed/64: Don't pre-map memory in KASLR code") set up a new page table in the decompressor stub, but without explicit mappings for boot_params and the kernel command line, relying on the #PF handler instead. This is fragile, as boot_params and the command line mappings are required for the main kernel. If EARLY_PRINTK and RANDOMIZE_BASE are disabled, a QEMU/OVMF boot never accesses the command line in the decompressor stub, and so it never gets mapped. The main kernel accesses it from the identity mapping if AMD_MEM_ENCRYPT is enabled, and will crash. Fix this by adding back the explicit mapping of boot_params and the command line. Note: the changes also removed the explicit mapping of the main kernel, with the result that .bss and .brk may not be in the identity mapping, but those don't get accessed by the main kernel before it switches to its own page tables. [ bp: Pass boot_params with a MOV %rsp... instead of PUSH/POP. Use block formatting for the comment. ] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Joerg Roedel <jroedel@suse.de> Link: https://lkml.kernel.org/r/20201016200404.1615994-1-nivedita@alum.mit.edu
| | * | | | | x86/head/64: Disable stack protection for head$(BITS).oArvind Sankar2020-10-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On 64-bit, the startup_64_setup_env() function added in 866b556efa12 ("x86/head/64: Install startup GDT") has stack protection enabled because of set_bringup_idt_handler(). This happens when CONFIG_STACKPROTECTOR_STRONG is enabled. It also currently needs CONFIG_AMD_MEM_ENCRYPT enabled because then set_bringup_idt_handler() is not an empty stub but that might change in the future, when the other vendor adds their similar technology. At this point, %gs is not yet initialized, and this doesn't cause a crash only because the #PF handler from the decompressor stub is still installed and handles the page fault. Disable stack protection for the whole file, and do it on 32-bit as well to avoid surprises. [ bp: Extend commit message with the exact explanation how it happens. ] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Joerg Roedel <jroedel@suse.de> Link: https://lkml.kernel.org/r/20201008191623.2881677-6-nivedita@alum.mit.edu
| | * | | | | x86/boot/64: Initialize 5-level paging variables earlierArvind Sankar2020-10-193-14/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ca0e22d4f011 ("x86/boot/compressed/64: Always switch to own page table") started using a new set of pagetables even without KASLR. After that commit, initialize_identity_maps() is called before the 5-level paging variables are setup in choose_random_location(), which will not work if 5-level paging is actually enabled. Fix this by moving the initialization of __pgtable_l5_enabled, pgdir_shift and ptrs_per_p4d into cleanup_trampoline(), which is called immediately after the finalization of whether the kernel is executing with 4- or 5-level paging. This will be earlier than anything that might require those variables, and keeps the 4- vs 5-level paging code all in one place. Fixes: ca0e22d4f011 ("x86/boot/compressed/64: Always switch to own page table") Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Joerg Roedel <jroedel@suse.de> Tested-by: Joerg Roedel <jroedel@suse.de> Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Link: https://lkml.kernel.org/r/20201010191110.4060905-1-nivedita@alum.mit.edu
| * | | | | | x86/uaccess: fix code generation in put_user()Rasmus Villemoes2020-10-231-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Quoting https://gcc.gnu.org/onlinedocs/gcc/Local-Register-Variables.html: You can define a local register variable and associate it with a specified register... The only supported use for this feature is to specify registers for input and output operands when calling Extended asm (see Extended Asm). This may be necessary if the constraints for a particular machine don't provide sufficient control to select the desired register. On 32-bit x86, this is used to ensure that gcc will put an 8-byte value into the %edx:%eax pair, while all other cases will just use the single register %eax (%rax on x86-64). While the _ASM_AX actually just expands to "%eax", note this comment next to get_user() which does something very similar: * The use of _ASM_DX as the register specifier is a bit of a * simplification, as gcc only cares about it as the starting point * and not size: for a 64-bit value it will use %ecx:%edx on 32 bits * (%ecx being the next register in gcc's x86 register sequence), and * %rdx on 64 bits. However, getting this to work requires that there is no code between the assignment to the local register variable and its use as an input to the asm() which can possibly clobber any of the registers involved - including evaluation of the expressions making up other inputs. In the current code, the ptr expression used directly as an input may cause such code to be emitted. For example, Sean Christopherson observed that with KASAN enabled and ptr being current->set_child_tid (from chedule_tail()), the load of current->set_child_tid causes a call to __asan_load8() to be emitted immediately prior to the __put_user_4 call, and Naresh Kamboju reports that various mmstress tests fail on KASAN-enabled builds. It's also possible to synthesize a broken case without KASAN if one uses "foo()" as the ptr argument, with foo being some "extern u64 __user *foo(void);" (though I don't know if that appears in real code). Fix it by making sure ptr gets evaluated before the assignment to __val_pu, and add a comment that __val_pu must be the last thing computed before the asm() is entered. Cc: Sean Christopherson <sean.j.christopherson@intel.com> Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org> Fixes: d55564cfc222 ("x86: Make __put_user() generate an out-of-line call") Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2020-10-2344-2359/+5013
| |\ \ \ \ \ \ | | | |/ / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "For x86, there is a new alternative and (in the future) more scalable implementation of extended page tables that does not need a reverse map from guest physical addresses to host physical addresses. For now it is disabled by default because it is still lacking a few of the existing MMU's bells and whistles. However it is a very solid piece of work and it is already available for people to hammer on it. Other updates: ARM: - New page table code for both hypervisor and guest stage-2 - Introduction of a new EL2-private host context - Allow EL2 to have its own private per-CPU variables - Support of PMU event filtering - Complete rework of the Spectre mitigation PPC: - Fix for running nested guests with in-kernel IRQ chip - Fix race condition causing occasional host hard lockup - Minor cleanups and bugfixes x86: - allow trapping unknown MSRs to userspace - allow userspace to force #GP on specific MSRs - INVPCID support on AMD - nested AMD cleanup, on demand allocation of nested SVM state - hide PV MSRs and hypercalls for features not enabled in CPUID - new test for MSR_IA32_TSC writes from host and guest - cleanups: MMU, CPUID, shared MSRs - LAPIC latency optimizations ad bugfixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (232 commits) kvm: x86/mmu: NX largepage recovery for TDP MMU kvm: x86/mmu: Don't clear write flooding count for direct roots kvm: x86/mmu: Support MMIO in the TDP MMU kvm: x86/mmu: Support write protection for nesting in tdp MMU kvm: x86/mmu: Support disabling dirty logging for the tdp MMU kvm: x86/mmu: Support dirty logging for the TDP MMU kvm: x86/mmu: Support changed pte notifier in tdp MMU kvm: x86/mmu: Add access tracking for tdp_mmu kvm: x86/mmu: Support invalidate range MMU notifier for TDP MMU kvm: x86/mmu: Allocate struct kvm_mmu_pages for all pages in TDP MMU kvm: x86/mmu: Add TDP MMU PF handler kvm: x86/mmu: Remove disallowed_hugepage_adjust shadow_walk_iterator arg kvm: x86/mmu: Support zapping SPTEs in the TDP MMU KVM: Cache as_id in kvm_memory_slot kvm: x86/mmu: Add functions to handle changed TDP SPTEs kvm: x86/mmu: Allocate and free TDP MMU roots kvm: x86/mmu: Init / Uninit the TDP MMU kvm: x86/mmu: Introduce tdp_iter KVM: mmu: extract spte.h and spte.c KVM: mmu: Separate updating a PTE from kvm_set_pte_rmapp ...
| | * | | | | kvm: x86/mmu: NX largepage recovery for TDP MMUBen Gardon2020-10-233-4/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When KVM maps a largepage backed region at a lower level in order to make it executable (i.e. NX large page shattering), it reduces the TLB performance of that region. In order to avoid making this degradation permanent, KVM must periodically reclaim shattered NX largepages by zapping them and allowing them to be rebuilt in the page fault handler. With this patch, the TDP MMU does not respect KVM's rate limiting on reclaim. It traverses the entire TDP structure every time. This will be addressed in a future patch. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-21-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Don't clear write flooding count for direct rootsBen Gardon2020-10-231-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Direct roots don't have a write flooding count because the guest can't affect that paging structure. Thus there's no need to clear the write flooding count on a fast CR3 switch for direct roots. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-20-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Support MMIO in the TDP MMUBen Gardon2020-10-233-21/+72
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to support MMIO, KVM must be able to walk the TDP paging structures to find mappings for a given GFN. Support this walk for the TDP MMU. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 v2: Thanks to Dan Carpenter and kernel test robot for finding that root was used uninitialized in get_mmio_spte. Signed-off-by: Ben Gardon <bgardon@google.com> Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Message-Id: <20201014182700.2888246-19-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Support write protection for nesting in tdp MMUBen Gardon2020-10-233-0/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To support nested virtualization, KVM will sometimes need to write protect pages which are part of a shadowed paging structure or are not writable in the shadowed paging structure. Add a function to write protect GFN mappings for this purpose. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-18-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Support disabling dirty logging for the tdp MMUBen Gardon2020-10-233-0/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dirty logging ultimately breaks down MMU mappings to 4k granularity. When dirty logging is no longer needed, these granaular mappings represent a useless performance penalty. When dirty logging is disabled, search the paging structure for mappings that could be re-constituted into a large page mapping. Zap those mappings so that they can be faulted in again at a higher mapping level. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-17-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Support dirty logging for the TDP MMUBen Gardon2020-10-234-5/+325
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dirty logging is a key feature of the KVM MMU and must be supported by the TDP MMU. Add support for both the write protection and PML dirty logging modes. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-16-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Support changed pte notifier in tdp MMUBen Gardon2020-10-233-1/+67
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to interoperate correctly with the rest of KVM and other Linux subsystems, the TDP MMU must correctly handle various MMU notifiers. Add a hook and handle the change_pte MMU notifier. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-15-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Add access tracking for tdp_mmuBen Gardon2020-10-233-7/+128
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to interoperate correctly with the rest of KVM and other Linux subsystems, the TDP MMU must correctly handle various MMU notifiers. The main Linux MM uses the access tracking MMU notifiers for swap and other features. Add hooks to handle the test/flush HVA (range) family of MMU notifiers. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-14-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Support invalidate range MMU notifier for TDP MMUBen Gardon2020-10-233-6/+86
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to interoperate correctly with the rest of KVM and other Linux subsystems, the TDP MMU must correctly handle various MMU notifiers. Add hooks to handle the invalidate range family of MMU notifiers. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-13-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Allocate struct kvm_mmu_pages for all pages in TDP MMUBen Gardon2020-10-232-3/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Attach struct kvm_mmu_pages to every page in the TDP MMU to track metadata, facilitate NX reclaim, and enable inproved parallelism of MMU operations in future patches. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-12-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Add TDP MMU PF handlerBen Gardon2020-10-235-37/+194
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add functions to handle page faults in the TDP MMU. These page faults are currently handled in much the same way as the x86 shadow paging based MMU, however the ordering of some operations is slightly different. Future patches will add eager NX splitting, a fast page fault handler, and parallel page faults. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-11-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Remove disallowed_hugepage_adjust shadow_walk_iterator argBen Gardon2020-10-212-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to avoid creating executable hugepages in the TDP MMU PF handler, remove the dependency between disallowed_hugepage_adjust and the shadow_walk_iterator. This will open the function up to being used by the TDP MMU PF handler in a future patch. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-10-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Support zapping SPTEs in the TDP MMUBen Gardon2020-10-215-0/+136
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add functions to zap SPTEs to the TDP MMU. These are needed to tear down TDP MMU roots properly and implement other MMU functions which require tearing down mappings. Future patches will add functions to populate the page tables, but as for this patch there will not be any work for these functions to do. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-8-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Add functions to handle changed TDP SPTEsBen Gardon2020-10-213-1/+115
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The existing bookkeeping done by KVM when a PTE is changed is spread around several functions. This makes it difficult to remember all the stats, bitmaps, and other subsystems that need to be updated whenever a PTE is modified. When a non-leaf PTE is marked non-present or becomes a leaf PTE, page table memory must also be freed. To simplify the MMU and facilitate the use of atomic operations on SPTEs in future patches, create functions to handle some of the bookkeeping required as a result of a change. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Allocate and free TDP MMU rootsBen Gardon2020-10-215-6/+146
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The TDP MMU must be able to allocate paging structure root pages and track the usage of those pages. Implement a similar, but separate system for root page allocation to that of the x86 shadow paging implementation. When future patches add synchronization model changes to allow for parallel page faults, these pages will need to be handled differently from the x86 shadow paging based MMU's root pages. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Init / Uninit the TDP MMUBen Gardon2020-10-215-1/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The TDP MMU offers an alternative mode of operation to the x86 shadow paging based MMU, optimized for running an L1 guest with TDP. The TDP MMU will require new fields that need to be initialized and torn down. Add hooks into the existing KVM MMU initialization process to do that initialization / cleanup. Currently the initialization and cleanup fucntions do not do very much, however more operations will be added in future patches. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Message-Id: <20201014182700.2888246-4-bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | kvm: x86/mmu: Introduce tdp_iterBen Gardon2020-10-213-1/+234
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The TDP iterator implements a pre-order traversal of a TDP paging structure. This iterator will be used in future patches to create an efficient implementation of the KVM MMU for the TDP case. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>