linux/arch/x86
David Vrabel 162e371712 x86/xen: safely map and unmap grant frames when in atomic context
arch_gnttab_map_frames() and arch_gnttab_unmap_frames() are called in
atomic context but were calling alloc_vm_area() which might sleep.

Also, if a driver attempts to allocate a grant ref from an interrupt
and the table needs expanding, then the CPU may already by in lazy MMU
mode and apply_to_page_range() will BUG when it tries to re-enable
lazy MMU mode.

These two functions are only used in PV guests.

Introduce arch_gnttab_init() to allocates the virtual address space in
advance.

Avoid the use of apply_to_page_range() by using saving and using the
array of PTE addresses from the alloc_vm_area() call.

N.B. 'alloc_vm_area' pre-allocates the pagetable so there is no need
to worry about having to do a PGD/PUD/PMD walk (like apply_to_page_range
does) and we can instead do set_pte.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
----
[v2: Add comment about alloc_vm_area]
[v3: Fix compile error found by 0-day bot]
2014-07-14 15:28:02 -04:00
..
boot x86, kaslr: boot-time selectable with hibernation 2014-06-16 23:30:44 +02:00
configs USB: remove CONFIG_USB_DEBUG from defconfig files 2014-05-28 09:40:45 -07:00
crypto crypto: sha512_ssse3 - fix byte count to bit count conversion 2014-06-25 21:55:02 +08:00
ia32 x86, vdso: Reimplement vdso.so preparation in build-time C 2014-05-05 13:18:51 -07:00
include ptrace,x86: force IRET path after a ptrace_stop() 2014-07-03 17:27:23 -07:00
kernel Merge branch 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-06-27 18:43:03 -07:00
kvm Merge commit '33b458d276bb' into kvm-master 2014-06-30 16:45:40 +02:00
lguest asmlinkage, x86: Add explicit __visible to arch/x86/* 2014-05-05 16:07:44 -07:00
lib Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-06-12 19:18:49 -07:00
math-emu asmlinkage, x86: Add explicit __visible to arch/x86/* 2014-05-05 16:07:44 -07:00
mm Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-06-12 19:18:49 -07:00
net net: filter: cleanup A/X name usage 2014-06-11 00:13:16 -07:00
oprofile x86, oprofile, nmi: Fix CPU hotplug callback registration 2014-03-20 13:43:43 +01:00
pci x86: enable DMA CMA with swiotlb 2014-06-04 16:53:57 -07:00
platform x86: intel-mid: add watchdog platform code for Merrifield 2014-06-10 21:48:20 +02:00
power asmlinkage, x86: Add explicit __visible to arch/x86/* 2014-05-05 16:07:44 -07:00
realmode x86/build: Supress realmode.bin is up to date message 2014-04-16 15:17:24 +02:00
syscalls x86, x32: Use compat shims for io_{setup,submit} 2014-05-04 17:49:22 -07:00
tools x86/build: Supress "Nothing to be done for ..." messages 2014-04-14 11:44:36 +02:00
um x86, vdso: Clean up 32-bit vs 64-bit vdso params 2014-05-05 13:18:40 -07:00
vdso x86-32, vdso: Fix vDSO build error due to missing align_vdso_addr() 2014-07-10 16:06:04 -07:00
video
xen x86/xen: safely map and unmap grant frames when in atomic context 2014-07-14 15:28:02 -04:00
.gitignore
Kbuild
Kconfig x86, kaslr: boot-time selectable with hibernation 2014-06-16 23:30:44 +02:00
Kconfig.cpu Merge branch 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-02 13:15:58 -07:00
Kconfig.debug x86/efi: Dump the EFI page table 2014-03-04 16:17:17 +00:00
Makefile x86-64, build: Fix stack protector Makefile breakage with 32-bit userland 2014-05-07 14:14:44 -07:00
Makefile.um
Makefile_32.cpu