Kirill A. Shutemov 16877a5570 x86/mm: Fix guard hole handling ...

There is a guard hole at the beginning of the kernel address space, also
used by hypervisors. It occupies 16 PGD entries.

This reserved range is not defined explicitely, it is calculated relative
to other entities: direct mapping and user space ranges.

The calculation got broken by recent changes of the kernel memory layout:
LDT remap range is now mapped before direct mapping and makes the
calculation invalid.

The breakage leads to crash on Xen dom0 boot[1].

Define the reserved range explicitely. It's part of kernel ABI (hypervisors
expect it to be stable) and must not depend on changes in the rest of
kernel memory layout.

[1] https://lists.xenproject.org/archives/html/xen-devel/2018-11/msg03313.html

Fixes: d52888aa27 ("x86/mm: Move LDT remap out of KASLR region on 5-level paging")
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: dave.hansen@linux.intel.com
Cc: luto@kernel.org
Cc: peterz@infradead.org
Cc: boris.ostrovsky@oracle.com
Cc: bhe@redhat.com
Cc: linux-mm@kvack.org
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20181130202328.65359-2-kirill.shutemov@linux.intel.com

2018-12-11 11:19:24 +01:00

..

apic.c

Merge branch 'WIP.x86/asm' into x86/urgent, because the topic is ready

2018-04-12 09:42:34 +02:00

debugfs.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

debugfs.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

efi.c

x86/xen: Add SPDX identifier in arch/x86/xen files

2018-09-03 16:50:33 +02:00

enlighten_hvm.c

x86/xen: Add SPDX identifier in arch/x86/xen files

2018-09-03 16:50:33 +02:00

enlighten_pv.c

mm: remove include/linux/bootmem.h

2018-10-31 08:54:16 -07:00

enlighten_pvh.c

Merge branch 'x86-grub2-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-10-23 16:31:33 +01:00

enlighten.c

Merge tag 'for-linus-4.20a-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2018-12-02 12:15:55 -08:00

grant-table.c

x86/xen: Add SPDX identifier in arch/x86/xen files

2018-09-03 16:50:33 +02:00

irq.c

x86/paravirt: Use a single ops structure

2018-09-03 16:50:35 +02:00

Kconfig

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

2018-10-23 17:54:58 +01:00

Makefile

x86/xen: Link platform-pci-unplug.o only if CONFIG_XEN_PVHVM

2018-09-03 16:50:33 +02:00

mmu_hvm.c

x86/paravirt: Use a single ops structure

2018-09-03 16:50:35 +02:00

mmu_pv.c

x86/mm: Fix guard hole handling

2018-12-11 11:19:24 +01:00

mmu.c

x86/xen: Add SPDX identifier in arch/x86/xen files

2018-09-03 16:50:33 +02:00

mmu.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

multicalls.c

xen/x86: add diagnostic printout to xen_mc_flush() in case of error

2018-11-29 17:53:16 +01:00

multicalls.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

p2m.c

Merge tag 'for-linus-4.20a-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2018-11-10 08:58:48 -06:00

pci-swiotlb-xen.c

x86/xen: Add SPDX identifier in arch/x86/xen files

2018-09-03 16:50:33 +02:00

platform-pci-unplug.c

xen/pvh: don't try to unplug emulated devices

2018-10-26 09:16:57 +02:00

pmu.c

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

2018-10-23 16:16:40 +01:00

pmu.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

setup.c

Revert "xen/balloon: Mark unallocated host memory as UNUSABLE"

2018-11-29 17:53:31 +01:00

smp_hvm.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

smp_pv.c

x86/stackprotector: Remove the call to boot_init_stack_canary() from cpu_startup_entry()

2018-10-22 04:07:24 +02:00

smp.c

x86/xen: Calculate __max_logical_packages on PV domains

2018-02-17 09:40:45 +01:00

smp.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

spinlock.c

x86/xen: cleanup includes in arch/x86/xen/spinlock.c

2018-11-22 16:47:50 +01:00

suspend_hvm.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

suspend_pv.c

x86/xen/time: Initialize pv xen time in init_hypervisor_platform()

2018-07-20 00:02:39 +02:00

suspend.c

x86/xen: Zero MSR_IA32_SPEC_CTRL before suspend

2018-02-28 16:03:19 +01:00

time.c

x86/paravirt: Use a single ops structure

2018-09-03 16:50:35 +02:00

trace.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

vdso.h

x86/xen: Add SPDX identifier in arch/x86/xen files

2018-09-03 16:50:33 +02:00

vga.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

xen-asm_32.S

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

xen-asm_64.S

x86/entry/64: Use the TSS sp2 slot for SYSCALL/SYSRET scratch space

2018-09-08 11:20:11 +02:00

xen-asm.S

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

xen-head.S

xen/pvh: Indicate XENFEAT_linux_rsdp_unrestricted to Xen

2018-04-10 09:22:22 -04:00

xen-ops.h

x86/xen: remove unused function xen_auto_xlated_memory_setup()

2018-08-20 14:46:18 -04:00

xen-pvh.S

xen/pvh: increase early stack size

2018-10-24 10:18:28 +02:00