kernel/arch/x86/include/asm/fixmap.h, branch linux-5.1.y

Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-10-23T16:54:58Z

Pull x86 paravirt updates from Ingo Molnar: "Two main changes: - Remove no longer used parts of the paravirt infrastructure and put large quantities of paravirt ops under a new config option PARAVIRT_XXL=y, which is selected by XEN_PV only. (Joergen Gross) - Enable PV spinlocks on Hyperv (Yi Sun)" * 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/hyperv: Enable PV qspinlock for Hyper-V x86/hyperv: Add GUEST_IDLE_MSR support x86/paravirt: Clean up native_patch() x86/paravirt: Prevent redefinition of SAVE_FLAGS macro x86/xen: Make xen_reservation_lock static x86/paravirt: Remove unneeded mmu related paravirt ops bits x86/paravirt: Move the Xen-only pv_mmu_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move the pv_irq_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move the Xen-only pv_cpu_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move items in pv_info under PARAVIRT_XXL umbrella x86/paravirt: Introduce new config option PARAVIRT_XXL x86/paravirt: Remove unused paravirt bits x86/paravirt: Use a single ops structure x86/paravirt: Remove clobbers from struct paravirt_patch_site x86/paravirt: Remove clobbers parameter from paravirt patch functions x86/paravirt: Make paravirt_patch_call() and paravirt_patch_jmp() static x86/xen: Add SPDX identifier in arch/x86/xen files x86/xen: Link platform-pci-unplug.o only if CONFIG_XEN_PVHVM x86/xen: Move pv specific parts of arch/x86/xen/mmu.c to mmu_pv.c x86/xen: Move pv irq related functions under CONFIG_XEN_PV umbrella

x86/mm: Expand static page table for fixmap space

2018-09-20T21:17:22Z

We met a kernel panic when enabling earlycon, which is due to the fixmap address of earlycon is not statically setup. Currently the static fixmap setup in head_64.S only covers 2M virtual address space, while it actually could be in 4M space with different kernel configurations, e.g. when VSYSCALL emulation is disabled. So increase the static space to 4M for now by defining FIXMAP_PMD_NUM to 2, and add a build time check to ensure that the fixmap is covered by the initial static page tables. Fixes: 1ad83c858c7d ("x86_64,vsyscall: Make vsyscall emulation configurable") Suggested-by: Thomas Gleixner Signed-off-by: Feng Tang Signed-off-by: Thomas Gleixner Tested-by: kernel test robot Reviewed-by: Juergen Gross (Xen parts) Cc: H Peter Anvin Cc: Peter Zijlstra Cc: Michal Hocko Cc: Yinghai Lu Cc: Dave Hansen Cc: Andi Kleen Cc: Andy Lutomirsky Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180920025828.23699-1-feng.tang@intel.com

x86/paravirt: Move the Xen-only pv_mmu_ops under the PARAVIRT_XXL umbrella

2018-09-03T14:50:37Z

Most of the paravirt ops defined in pv_mmu_ops are for Xen PV guests only. Define them only if CONFIG_PARAVIRT_XXL is set. Signed-off-by: Juergen Gross Signed-off-by: Thomas Gleixner Cc: xen-devel@lists.xenproject.org Cc: virtualization@lists.linux-foundation.org Cc: akataria@vmware.com Cc: rusty@rustcorp.com.au Cc: boris.ostrovsky@oracle.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180828074026.820-15-jgross@suse.com

x86/mm: Fix overlap of i386 CPU_ENTRY_AREA with FIX_BTMAP

2018-01-30T14:30:35Z

Since commit 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap"), i386's CPU_ENTRY_AREA has been mapped to the memory area just below FIXADDR_START. But already immediately before FIXADDR_START is the FIX_BTMAP area, which means that early_ioremap can collide with the entry area. It's especially bad on PAE where FIX_BTMAP_BEGIN gets aligned to exactly match CPU_ENTRY_AREA_BASE, so the first early_ioremap slot clobbers the IDT and causes interrupts during early boot to reset the system. The overlap wasn't a problem before the CPU entry area was introduced, as the fixmap has classically been preceded by the pkmap or vmalloc areas, neither of which is used until early_ioremap is out of the picture. Relocate CPU_ENTRY_AREA to below FIX_BTMAP, not just below the permanent fixmap area. Fixes: commit 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") Signed-off-by: William Grant Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/7041d181-a019-e8b9-4e4e-48215f841e2c@canonical.com

x86/cpu_entry_area: Move it out of the fixmap

2017-12-22T19:13:05Z

Put the cpu_entry_area into a separate P4D entry. The fixmap gets too big and 0-day already hit a case where the fixmap PTEs were cleared by cleanup_highmap(). Aside of that the fixmap API is a pain as it's all backwards. Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

x86/cpu_entry_area: Move it to a separate unit

2017-12-22T19:13:04Z

Separate the cpu_entry_area code out of cpu/common.c and the fixmap. Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Signed-off-by: Ingo Molnar

x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack

2017-12-22T19:13:02Z

If the kernel oopses while on the trampoline stack, it will print "" even if SYSENTER is not involved. That is rather confusing. The "SYSENTER" stack is used for a lot more than SYSENTER now. Give it a better string to display in stack dumps, and rename the kernel code to match. Also move the 32-bit code over to the new naming even though it still uses the entry stack only for SYSENTER. Signed-off-by: Dave Hansen Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Signed-off-by: Ingo Molnar

x86/entry/64: Make cpu_entry_area.tss read-only

2017-12-17T13:27:52Z

The TSS is a fairly juicy target for exploits, and, now that the TSS is in the cpu_entry_area, it's no longer protected by kASLR. Make it read-only on x86_64. On x86_32, it can't be RO because it's written by the CPU during task switches, and we use a task gate for double faults. I'd also be nervous about errata if we tried to make it RO even on configurations without double fault handling. [ tglx: AMD confirmed that there is no problem on 64-bit with TSS RO. So it's probably safe to assume that it's a non issue, though Intel might have been creative in that area. Still waiting for confirmation. ] Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Reviewed-by: Borislav Petkov Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Kees Cook Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Link: https://lkml.kernel.org/r/20171204150606.733700132@linutronix.de Signed-off-by: Ingo Molnar

x86/entry: Clean up the SYSENTER_stack code

2017-12-17T13:27:51Z

The existing code was a mess, mainly because C arrays are nasty. Turn SYSENTER_stack into a struct, add a helper to find it, and do all the obvious cleanups this enables. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Reviewed-by: Thomas Gleixner Reviewed-by: Borislav Petkov Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Link: https://lkml.kernel.org/r/20171204150606.653244723@linutronix.de Signed-off-by: Ingo Molnar

x86/entry/64: Move the IST stacks into struct cpu_entry_area

2017-12-17T13:27:51Z

The IST stacks are needed when an IST exception occurs and are accessed before any kernel code at all runs. Move them into struct cpu_entry_area. The IST stacks are unlike the rest of cpu_entry_area: they're used even for entries from kernel mode. This means that they should be set up before we load the final IDT. Move cpu_entry_area setup to trap_init() for the boot CPU and set it up for all possible CPUs at once in native_smp_prepare_cpus(). Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Reviewed-by: Thomas Gleixner Reviewed-by: Borislav Petkov Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Link: https://lkml.kernel.org/r/20171204150606.480598743@linutronix.de Signed-off-by: Ingo Molnar