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* Merge tag 'stable/for-linus-3.8-rc0-bugfix-tag' of ↵Linus Torvalds2012-12-182-4/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen bugfixes from Konrad Rzeszutek Wilk: "Two fixes. One of them is caused by the recent change introduced by the 'x86-bsp-hotplug-for-linus' tip tree that inhibited bootup (old function does not do what it used to do). The other one is just a vanilla bug. - Fix to bootup regression introduced by 'x86-bsp-hotplug-for-linus' tip branch. - Fix to vcpu hotplug code." * tag 'stable/for-linus-3.8-rc0-bugfix-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/vcpu: Fix vcpu restore path. xen: Add EVTCHNOP_reset in Xen interface header files. xen/smp: Use smp_store_boot_cpu_info() to store cpu info for BSP during boot time.
| * xen/vcpu: Fix vcpu restore path.Wei Liu2012-12-181-3/+4
| | | | | | | | | | | | | | | | | | The runstate of vcpu should be restored for all possible cpus, as well as the vcpu info placement. Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * xen/smp: Use smp_store_boot_cpu_info() to store cpu info for BSP during boot ↵Konrad Rzeszutek Wilk2012-12-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | time. Git commit 30106c174311b8cfaaa3186c7f6f9c36c62d17da ("x86, hotplug: Support functions for CPU0 online/offline") alters what the call to smp_store_cpu_info() does. For BSP we should use the smp_store_boot_cpu_info() and for secondary CPU's the old variant of smp_store_cpu_info() should be used. This fixes the regression introduced by said commit. Reported-and-Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | Merge tag 'stable/for-linus-3.8-rc0-tag' of ↵Linus Torvalds2012-12-135-29/+95
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen updates from Konrad Rzeszutek Wilk: - Add necessary infrastructure to make balloon driver work under ARM. - Add /dev/xen/privcmd interfaces to work with ARM and PVH. - Improve Xen PCIBack wild-card parsing. - Add Xen ACPI PAD (Processor Aggregator) support - so can offline/ online sockets depending on the power consumption. - PVHVM + kexec = use an E820_RESV region for the shared region so we don't overwrite said region during kexec reboot. - Cleanups, compile fixes. Fix up some trivial conflicts due to the balloon driver now working on ARM, and there were changes next to the previous work-arounds that are now gone. * tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/PVonHVM: fix compile warning in init_hvm_pv_info xen: arm: implement remap interfaces needed for privcmd mappings. xen: correctly use xen_pfn_t in remap_domain_mfn_range. xen: arm: enable balloon driver xen: balloon: allow PVMMU interfaces to be compiled out xen: privcmd: support autotranslated physmap guests. xen: add pages parameter to xen_remap_domain_mfn_range xen/acpi: Move the xen_running_on_version_or_later function. xen/xenbus: Remove duplicate inclusion of asm/xen/hypervisor.h xen/acpi: Fix compile error by missing decleration for xen_domain. xen/acpi: revert pad config check in xen_check_mwait xen/acpi: ACPI PAD driver xen-pciback: reject out of range inputs xen-pciback: simplify and tighten parsing of device IDs xen PVonHVM: use E820_Reserved area for shared_info
| * Merge branch 'arm-privcmd-for-3.8' of ↵Konrad Rzeszutek Wilk2012-11-302-2/+16
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://xenbits.xen.org/people/ianc/linux into stable/for-linus-3.8 * 'arm-privcmd-for-3.8' of git://xenbits.xen.org/people/ianc/linux: xen: arm: implement remap interfaces needed for privcmd mappings. xen: correctly use xen_pfn_t in remap_domain_mfn_range. xen: arm: enable balloon driver xen: balloon: allow PVMMU interfaces to be compiled out xen: privcmd: support autotranslated physmap guests. xen: add pages parameter to xen_remap_domain_mfn_range Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| | * xen: correctly use xen_pfn_t in remap_domain_mfn_range.Ian Campbell2012-11-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For Xen on ARM a PFN is 64 bits so we need to use the appropriate type here. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v2: include the necessary header, Reported-by: Fengguang Wu <fengguang.wu@intel.com> ]
| | * xen: balloon: allow PVMMU interfaces to be compiled outIan Campbell2012-11-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ARM platform has no concept of PVMMU and therefor no HYPERVISOR_update_va_mapping et al. Allow this code to be compiled out when not required. In some similar situations (e.g. P2M) we have defined dummy functions to avoid this, however I think we can/should draw the line at dummying out actual hypercalls. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| | * xen: add pages parameter to xen_remap_domain_mfn_rangeIan Campbell2012-11-291-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also introduce xen_unmap_domain_mfn_range. These are the parts of Mukesh's "xen/pvh: Implement MMU changes for PVH" which are also needed as a baseline for ARM privcmd support. The original patch was: Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> This derivative is also: Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
| * | xen/PVonHVM: fix compile warning in init_hvm_pv_infoOlaf Hering2012-11-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After merging the xen-two tree, today's linux-next build (x86_64 allmodconfig) produced this warning: arch/x86/xen/enlighten.c: In function 'init_hvm_pv_info': arch/x86/xen/enlighten.c:1617:16: warning: unused variable 'ebx' [-Wunused-variable] arch/x86/xen/enlighten.c:1617:11: warning: unused variable 'eax' [-Wunused-variable] Introduced by commit 9d02b43dee0d ("xen PVonHVM: use E820_Reserved area for shared_info"). Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/acpi: Move the xen_running_on_version_or_later function.Konrad Rzeszutek Wilk2012-11-281-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As on ia64 builds we get: include/xen/interface/version.h: In function 'xen_running_on_version_or_later': include/xen/interface/version.h:76: error: implicit declaration of function 'HYPERVISOR_xen_version' We can later on make this function exportable if there are modules using part of it. For right now the only two users are built-in. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | xen/acpi: revert pad config check in xen_check_mwaitLiu, Jinsong2012-11-261-2/+8
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | With Xen acpi pad logic added into kernel, we can now revert xen mwait related patch df88b2d96e36d9a9e325bfcd12eb45671cbbc937 ("xen/enlighten: Disable MWAIT_LEAF so that acpi-pad won't be loaded. "). The reason is, when running under newer Xen platform, Xen pad driver would be early loaded, so native pad driver would fail to be loaded, and hence no mwait/monitor #UD risk again. Another point is, only Xen4.2 or later support Xen acpi pad, so we won't expose mwait cpuid capability when running under older Xen platform. Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * xen PVonHVM: use E820_Reserved area for shared_infoOlaf Hering2012-11-023-24/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a respin of 00e37bdb0113a98408de42db85be002f21dbffd3 ("xen PVonHVM: move shared_info to MMIO before kexec"). Currently kexec in a PVonHVM guest fails with a triple fault because the new kernel overwrites the shared info page. The exact failure depends on the size of the kernel image. This patch moves the pfn from RAM into an E820 reserved memory area. The pfn containing the shared_info is located somewhere in RAM. This will cause trouble if the current kernel is doing a kexec boot into a new kernel. The new kernel (and its startup code) can not know where the pfn is, so it can not reserve the page. The hypervisor will continue to update the pfn, and as a result memory corruption occours in the new kernel. The toolstack marks the memory area FC000000-FFFFFFFF as reserved in the E820 map. Within that range newer toolstacks (4.3+) will keep 1MB starting from FE700000 as reserved for guest use. Older Xen4 toolstacks will usually not allocate areas up to FE700000, so FE700000 is expected to work also with older toolstacks. In Xen3 there is no reserved area at a fixed location. If the guest is started on such old hosts the shared_info page will be placed in RAM. As a result kexec can not be used. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | x86, 386 removal: Remove CONFIG_CMPXCHGH. Peter Anvin2012-11-291-1/+1
| | | | | | | | | | | | | | | | All 486+ CPUs support CMPXCHG, so remove the fallback 386 support code. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1354132230-21854-3-git-send-email-hpa@linux.intel.com
* | xen/mmu: Use Xen specific TLB flush instead of the generic one.Konrad Rzeszutek Wilk2012-10-311-1/+20
|/ | | | | | | | | | | | | | | | | | | | | | As Mukesh explained it, the MMUEXT_TLB_FLUSH_ALL allows the hypervisor to do a TLB flush on all active vCPUs. If instead we were using the generic one (which ends up being xen_flush_tlb) we end up making the MMUEXT_TLB_FLUSH_LOCAL hypercall. But before we make that hypercall the kernel will IPI all of the vCPUs (even those that were asleep from the hypervisor perspective). The end result is that we needlessly wake them up and do a TLB flush when we can just let the hypervisor do it correctly. This patch gives around 50% speed improvement when migrating idle guest's from one host to another. Oracle-bug: 14630170 CC: stable@vger.kernel.org Tested-by: Jingjie Jiang <jingjie.jiang@oracle.com> Suggested-by: Mukesh Rathor <mukesh.rathor@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* Merge commit 'v3.7-rc1' into stable/for-linus-3.7Konrad Rzeszutek Wilk2012-10-195-22/+22
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * commit 'v3.7-rc1': (10892 commits) Linux 3.7-rc1 x86, boot: Explicitly include autoconf.h for hostprogs perf: Fix UAPI fallout ARM: config: make sure that platforms are ordered by option string ARM: config: sort select statements alphanumerically UAPI: (Scripted) Disintegrate include/linux/byteorder UAPI: (Scripted) Disintegrate include/linux UAPI: Unexport linux/blk_types.h UAPI: Unexport part of linux/ppp-comp.h perf: Handle new rbtree implementation procfs: don't need a PATH_MAX allocation to hold a string representation of an int vfs: embed struct filename inside of names_cache allocation if possible audit: make audit_inode take struct filename vfs: make path_openat take a struct filename pointer vfs: turn do_path_lookup into wrapper around struct filename variant audit: allow audit code to satisfy getname requests from its names_list vfs: define struct filename and have getname() return it btrfs: Fix compilation with user namespace support enabled userns: Fix posix_acl_file_xattr_userns gid conversion userns: Properly print bluetooth socket uids ...
| * Merge tag 'stable/for-linus-3.7-rc0-tag' of ↵Linus Torvalds2012-10-122-1/+58
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen fixes from Konrad Rzeszutek Wilk: "This has four bug-fixes and one tiny feature that I forgot to put initially in my tree due to oversight. The feature is for kdump kernels to speed up the /proc/vmcore reading. There is a ram_is_pfn helper function that the different platforms can register for. We are now doing that. The bug-fixes cover some embarrassing struct pv_cpu_ops variables being set to NULL on Xen (but not baremetal). We had a similar issue in the past with {write|read}_msr_safe and this fills the three missing ones. The other bug-fix is to make the console output (hvc) be capable of dealing with misbehaving backends and not fall flat on its face. Lastly, a quirk for older XenBus implementations that came with an ancient v3.4 hypervisor (so RHEL5 based) - reading of certain non-existent attributes just hangs the guest during bootup - so we take precaution of not doing that on such older installations. Feature: - Register a pfn_is_ram helper to speed up reading of /proc/vmcore. Bug-fixes: - Three pvops call for Xen were undefined causing BUG_ONs. - Add a quirk so that the shutdown watches (used by kdump) are not used with older Xen (3.4). - Fix ungraceful state transition for the HVC console." * tag 'stable/for-linus-3.7-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pv-on-hvm kexec: add quirk for Xen 3.4 and shutdown watches. xen/bootup: allow {read|write}_cr8 pvops call. xen/bootup: allow read_tscp call for Xen PV guests. xen pv-on-hvm: add pfn_is_ram helper for kdump xen/hvc: handle backend CLOSED without CLOSING
| * | mm: kill vma flag VM_RESERVED and mm->reserved_vm counterKonstantin Khlebnikov2012-10-091-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A long time ago, in v2.4, VM_RESERVED kept swapout process off VMA, currently it lost original meaning but still has some effects: | effect | alternative flags -+------------------------+--------------------------------------------- 1| account as reserved_vm | VM_IO 2| skip in core dump | VM_IO, VM_DONTDUMP 3| do not merge or expand | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP 4| do not mlock | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP This patch removes reserved_vm counter from mm_struct. Seems like nobody cares about it, it does not exported into userspace directly, it only reduces total_vm showed in proc. Thus VM_RESERVED can be replaced with VM_IO or pair VM_DONTEXPAND | VM_DONTDUMP. remap_pfn_range() and io_remap_pfn_range() set VM_IO|VM_DONTEXPAND|VM_DONTDUMP. remap_vmalloc_range() set VM_DONTEXPAND | VM_DONTDUMP. [akpm@linux-foundation.org: drivers/vfio/pci/vfio_pci.c fixup] Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | Merge tag 'stable/for-linus-3.7-arm-tag' of ↵Linus Torvalds2012-10-073-1/+2
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull ADM Xen support from Konrad Rzeszutek Wilk: Features: * Allow a Linux guest to boot as initial domain and as normal guests on Xen on ARM (specifically ARMv7 with virtualized extensions). PV console, block and network frontend/backends are working. Bug-fixes: * Fix compile linux-next fallout. * Fix PVHVM bootup crashing. The Xen-unstable hypervisor (so will be 4.3 in a ~6 months), supports ARMv7 platforms. The goal in implementing this architecture is to exploit the hardware as much as possible. That means use as little as possible of PV operations (so no PV MMU) - and use existing PV drivers for I/Os (network, block, console, etc). This is similar to how PVHVM guests operate in X86 platform nowadays - except that on ARM there is no need for QEMU. The end result is that we share a lot of the generic Xen drivers and infrastructure. Details on how to compile/boot/etc are available at this Wiki: http://wiki.xen.org/wiki/Xen_ARMv7_with_Virtualization_Extensions and this blog has links to a technical discussion/presentations on the overall architecture: http://blog.xen.org/index.php/2012/09/21/xensummit-sessions-new-pvh-virtualisation-mode-for-arm-cortex-a15arm-servers-and-x86/ * tag 'stable/for-linus-3.7-arm-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (21 commits) xen/xen_initial_domain: check that xen_start_info is initialized xen: mark xen_init_IRQ __init xen/Makefile: fix dom-y build arm: introduce a DTS for Xen unprivileged virtual machines MAINTAINERS: add myself as Xen ARM maintainer xen/arm: compile netback xen/arm: compile blkfront and blkback xen/arm: implement alloc/free_xenballooned_pages with alloc_pages/kfree xen/arm: receive Xen events on ARM xen/arm: initialize grant_table on ARM xen/arm: get privilege status xen/arm: introduce CONFIG_XEN on ARM xen: do not compile manage, balloon, pci, acpi, pcpu and cpu_hotplug on ARM xen/arm: Introduce xen_ulong_t for unsigned long xen/arm: Xen detection and shared_info page mapping docs: Xen ARM DT bindings xen/arm: empty implementation of grant_table arch specific functions xen/arm: sync_bitops xen/arm: page.h definitions xen/arm: hypercalls ...
| * \ \ Merge tag 'stable/for-linus-3.7-x86-tag' of ↵Linus Torvalds2012-10-0310-59/+378
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen update from Konrad Rzeszutek Wilk: "Features: - When hotplugging PCI devices in a PV guest we can allocate Xen-SWIOTLB later. - Cleanup Xen SWIOTLB. - Support pages out grants from HVM domains in the backends. - Support wild cards in xen-pciback.hide=(BDF) arguments. - Update grant status updates with upstream hypervisor. - Boot PV guests with more than 128GB. - Cleanup Xen MMU code/add comments. - Obtain XENVERS using a preferred method. - Lay out generic changes to support Xen ARM. - Allow privcmd ioctl for HVM (used to do only PV). - Do v2 of mmap_batch for privcmd ioctls. - If hypervisor saves the LED keyboard light - we will now instruct the kernel about its state. Fixes: - More fixes to Xen PCI backend for various calls/FLR/etc. - With more than 4GB in a 64-bit PV guest disable native SWIOTLB. - Fix up smatch warnings. - Fix up various return values in privmcmd and mm." * tag 'stable/for-linus-3.7-x86-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (48 commits) xen/pciback: Restore the PCI config space after an FLR. xen-pciback: properly clean up after calling pcistub_device_find() xen/vga: add the xen EFI video mode support xen/x86: retrieve keyboard shift status flags from hypervisor. xen/gndev: Xen backend support for paged out grant targets V4. xen-pciback: support wild cards in slot specifications xen/swiotlb: Fix compile warnings when using plain integer instead of NULL pointer. xen/swiotlb: Remove functions not needed anymore. xen/pcifront: Use Xen-SWIOTLB when initting if required. xen/swiotlb: For early initialization, return zero on success. xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used. xen/swiotlb: Move the error strings to its own function. xen/swiotlb: Move the nr_tbl determination in its own function. xen/arm: compile and run xenbus xen: resynchronise grant table status codes with upstream xen/privcmd: return -EFAULT on error xen/privcmd: Fix mmap batch ioctl error status copy back. xen/privcmd: add PRIVCMD_MMAPBATCH_V2 ioctl xen/mm: return more precise error from xen_remap_domain_range() xen/mmu: If the revector fails, don't attempt to revector anything else. ...
| * \ \ \ Merge branch 'x86-platform-for-linus' of ↵Linus Torvalds2012-10-011-11/+7
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/platform changes from Ingo Molnar: "This cleans up some Xen-induced pagetable init code uglies, by generalizing new platform callbacks and state: x86_init.paging.*" * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Document x86_init.paging.pagetable_init() x86: xen: Cleanup and remove x86_init.paging.pagetable_setup_done() x86: Move paging_init() call to x86_init.paging.pagetable_init() x86: Rename pagetable_setup_start() to pagetable_init() x86: Remove base argument from x86_init.paging.pagetable_setup_start
| * \ \ \ \ Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds2012-10-011-4/+2
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/asm changes from Ingo Molnar: "The one change that stands out is the alternatives patching change that prevents us from ever patching back instructions from SMP to UP: this simplifies things and speeds up CPU hotplug. Other than that it's smaller fixes, cleanups and improvements." * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Unspaghettize do_trap() x86_64: Work around old GAS bug x86: Use REP BSF unconditionally x86: Prefer TZCNT over BFS x86/64: Adjust types of temporaries used by ffs()/fls()/fls64() x86: Drop unnecessary kernel_eflags variable on 64-bit x86/smp: Don't ever patch back to UP if we unplug cpus
| | * | | | | x86/smp: Don't ever patch back to UP if we unplug cpusRusty Russell2012-08-231-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We still patch SMP instructions to UP variants if we boot with a single CPU, but not at any other time. In particular, not if we unplug CPUs to return to a single cpu. Paul McKenney points out: mean offline overhead is 6251/48=130.2 milliseconds. If I remove the alternatives_smp_switch() from the offline path [...] the mean offline overhead is 550/42=13.1 milliseconds Basically, we're never going to get those 120ms back, and the code is pretty messy. We get rid of: 1) The "smp-alt-once" boot option. It's actually "smp-alt-boot", the documentation is wrong. It's now the default. 2) The skip_smp_alternatives flag used by suspend. 3) arch_disable_nonboot_cpus_begin() and arch_disable_nonboot_cpus_end() which were only used to set this one flag. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul McKenney <paul.mckenney@us.ibm.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/87vcgwwive.fsf@rustcorp.com.au Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | Merge tag 'stable/for-linus-3.6-rc1-tag' of ↵Linus Torvalds2012-08-161-0/+5
| | |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen fix from Konrad Rzeszutek Wilk: "Way back in v3.5 we added a mechanism to populate back pages that were released (they overlapped with MMIO regions), but neglected to reserve the proper amount of virtual space for extend_brk to work properly. Coincidentally some other commit aligned the _brk space to larger area so I didn't trigger this until it was run on a machine with more than 2GB of MMIO space." * On machines with large MMIO/PCI E820 spaces we fail to boot b/c we failed to pre-allocate large enough virtual space for extend_brk. * tag 'stable/for-linus-3.6-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back.
| * | | | | | | xen/boot: Disable NUMA for PV guests.Konrad Rzeszutek Wilk2012-09-241-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hypervisor is in charge of allocating the proper "NUMA" memory and dealing with the CPU scheduler to keep them bound to the proper NUMA node. The PV guests (and PVHVM) have no inkling of where they run and do not need to know that right now. In the future we will need to inject NUMA configuration data (if a guest spans two or more NUMA nodes) so that the kernel can make the right choices. But those patches are not yet present. In the meantime, disable the NUMA capability in the PV guest, which also fixes a bootup issue. Andre says: "we see Dom0 crashes due to the kernel detecting the NUMA topology not by ACPI, but directly from the northbridge (CONFIG_AMD_NUMA). This will detect the actual NUMA config of the physical machine, but will crash about the mismatch with Dom0's virtual memory. Variation of the theme: Dom0 sees what it's not supposed to see. This happens with the said config option enabled and on a machine where this scanning is still enabled (K8 and Fam10h, not Bulldozer class) We have this dump then: NUMA: Warning: node ids are out of bound, from=-1 to=-1 distance=10 Scanning NUMA topology in Northbridge 24 Number of physical nodes 4 Node 0 MemBase 0000000000000000 Limit 0000000040000000 Node 1 MemBase 0000000040000000 Limit 0000000138000000 Node 2 MemBase 0000000138000000 Limit 00000001f8000000 Node 3 MemBase 00000001f8000000 Limit 0000000238000000 Initmem setup node 0 0000000000000000-0000000040000000 NODE_DATA [000000003ffd9000 - 000000003fffffff] Initmem setup node 1 0000000040000000-0000000138000000 NODE_DATA [0000000137fd9000 - 0000000137ffffff] Initmem setup node 2 0000000138000000-00000001f8000000 NODE_DATA [00000001f095e000 - 00000001f0984fff] Initmem setup node 3 00000001f8000000-0000000238000000 Cannot find 159744 bytes in node 3 BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81d220e6>] __alloc_bootmem_node+0x43/0x96 Pid: 0, comm: swapper Not tainted 3.3.6 #1 AMD Dinar/Dinar RIP: e030:[<ffffffff81d220e6>] [<ffffffff81d220e6>] __alloc_bootmem_node+0x43/0x96 .. snip.. [<ffffffff81d23024>] sparse_early_usemaps_alloc_node+0x64/0x178 [<ffffffff81d23348>] sparse_init+0xe4/0x25a [<ffffffff81d16840>] paging_init+0x13/0x22 [<ffffffff81d07fbb>] setup_arch+0x9c6/0xa9b [<ffffffff81683954>] ? printk+0x3c/0x3e [<ffffffff81d01a38>] start_kernel+0xe5/0x468 [<ffffffff81d012cf>] x86_64_start_reservations+0xba/0xc1 [<ffffffff81007153>] ? xen_setup_runstate_info+0x2c/0x36 [<ffffffff81d050ee>] xen_start_kernel+0x565/0x56c " so we just disable NUMA scanning by setting numa_off=1. CC: stable@vger.kernel.org Reported-and-Tested-by: Andre Przywara <andre.przywara@amd.com> Acked-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | | xen/boot: Disable BIOS SMP MP table search.Konrad Rzeszutek Wilk2012-09-191-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the initial domain we are able to search/map certain regions of memory to harvest configuration data. For all low-level we use ACPI tables - for interrupts we use exclusively ACPI _PRT (so DSDT) and MADT for INT_SRC_OVR. The SMP MP table is not used at all. As a matter of fact we do not even support machines that only have SMP MP but no ACPI tables. Lets follow how Moorestown does it and just disable searching for BIOS SMP tables. This also fixes an issue on HP Proliant BL680c G5 and DL380 G6: 9f->100 for 1:1 PTE Freeing 9f-100 pfn range: 97 pages freed 1-1 mapping on 9f->100 .. snip.. e820: BIOS-provided physical RAM map: Xen: [mem 0x0000000000000000-0x000000000009efff] usable Xen: [mem 0x000000000009f400-0x00000000000fffff] reserved Xen: [mem 0x0000000000100000-0x00000000cfd1dfff] usable .. snip.. Scan for SMP in [mem 0x00000000-0x000003ff] Scan for SMP in [mem 0x0009fc00-0x0009ffff] Scan for SMP in [mem 0x000f0000-0x000fffff] found SMP MP-table at [mem 0x000f4fa0-0x000f4faf] mapped at [ffff8800000f4fa0] (XEN) mm.c:908:d0 Error getting mfn 100 (pfn 5555555555555555) from L1 entry 0000000000100461 for l1e_owner=0, pg_owner=0 (XEN) mm.c:4995:d0 ptwr_emulate: could not get_page_from_l1e() BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81ac07e2>] xen_set_pte_init+0x66/0x71 . snip.. Pid: 0, comm: swapper Not tainted 3.6.0-rc6upstream-00188-gb6fb969-dirty #2 HP ProLiant BL680c G5 .. snip.. Call Trace: [<ffffffff81ad31c6>] __early_ioremap+0x18a/0x248 [<ffffffff81624731>] ? printk+0x48/0x4a [<ffffffff81ad32ac>] early_ioremap+0x13/0x15 [<ffffffff81acc140>] get_mpc_size+0x2f/0x67 [<ffffffff81acc284>] smp_scan_config+0x10c/0x136 [<ffffffff81acc2e4>] default_find_smp_config+0x36/0x5a [<ffffffff81ac3085>] setup_arch+0x5b3/0xb5b [<ffffffff81624731>] ? printk+0x48/0x4a [<ffffffff81abca7f>] start_kernel+0x90/0x390 [<ffffffff81abc356>] x86_64_start_reservations+0x131/0x136 [<ffffffff81abfa83>] xen_start_kernel+0x65f/0x661 (XEN) Domain 0 crashed: 'noreboot' set - not rebooting. which is that ioremap would end up mapping 0xff using _PAGE_IOMAP (which is what early_ioremap sticks as a flag) - which meant we would get MFN 0xFF (pte ff461, which is OK), and then it would also map 0x100 (b/c ioremap tries to get page aligned request, and it was trying to map 0xf4fa0 + PAGE_SIZE - so it mapped the next page) as _PAGE_IOMAP. Since 0x100 is actually a RAM page, and the _PAGE_IOMAP bypasses the P2M lookup we would happily set the PTE to 1000461. Xen would deny the request since we do not have access to the Machine Frame Number (MFN) of 0x100. The P2M[0x100] is for example 0x80140. CC: stable@vger.kernel.org Fixes-Oracle-Bugzilla: https://bugzilla.oracle.com/bugzilla/show_bug.cgi?id=13665 Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | | xen/m2p: do not reuse kmap_op->dev_bus_addrStefano Stabellini2012-09-121-16/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the caller passes a valid kmap_op to m2p_add_override, we use kmap_op->dev_bus_addr to store the original mfn, but dev_bus_addr is part of the interface with Xen and if we are batching the hypercalls it might not have been written by the hypervisor yet. That means that later on Xen will write to it and we'll think that the original mfn is actually what Xen has written to it. Rather than "stealing" struct members from kmap_op, keep using page->index to store the original mfn and add another parameter to m2p_remove_override to get the corresponding kmap_op instead. It is now responsibility of the caller to keep track of which kmap_op corresponds to a particular page in the m2p_override (gntdev, the only user of this interface that passes a valid kmap_op, is already doing that). CC: stable@kernel.org Reported-and-Tested-By: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | | | xen/x86: remove duplicated include from enlighten.cWei Yongjun2012-10-191-2/+0
| |_|_|_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove duplicated include. dpatch engine is used to auto generate this patch. (https://github.com/weiyj/dpatch) CC: stable@vger.kernel.org Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | | xen/bootup: allow {read|write}_cr8 pvops call.Konrad Rzeszutek Wilk2012-10-121-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We actually do not do anything about it. Just return a default value of zero and if the kernel tries to write anything but 0 we BUG_ON. This fixes the case when an user tries to suspend the machine and it blows up in save_processor_state b/c 'read_cr8' is set to NULL and we get: kernel BUG at /home/konrad/ssd/linux/arch/x86/include/asm/paravirt.h:100! invalid opcode: 0000 [#1] SMP Pid: 2687, comm: init.late Tainted: G O 3.6.0upstream-00002-gac264ac-dirty #4 Bochs Bochs RIP: e030:[<ffffffff814d5f42>] [<ffffffff814d5f42>] save_processor_state+0x212/0x270 .. snip.. Call Trace: [<ffffffff810733bf>] do_suspend_lowlevel+0xf/0xac [<ffffffff8107330c>] ? x86_acpi_suspend_lowlevel+0x10c/0x150 [<ffffffff81342ee2>] acpi_suspend_enter+0x57/0xd5 CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | | xen/bootup: allow read_tscp call for Xen PV guests.Konrad Rzeszutek Wilk2012-10-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hypervisor will trap it. However without this patch, we would crash as the .read_tscp is set to NULL. This patch fixes it and sets it to the native_read_tscp call. CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | | xen pv-on-hvm: add pfn_is_ram helper for kdumpOlaf Hering2012-10-041-0/+41
| |_|_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Register pfn_is_ram helper speed up reading /proc/vmcore in the kdump kernel. See commit message of 997c136f518c ("fs/proc/vmcore.c: add hook to read_from_oldmem() to check for non-ram pages") for details. It makes use of a new hvmop HVMOP_get_mem_type which was introduced in xen 4.2 (23298:26413986e6e0) and backported to 4.1.1. The new function is currently only enabled for reading /proc/vmcore. Later it will be used also for the kexec kernel. Since that requires more changes in the generic kernel make it static for the time being. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | Merge branch 'xenarm-for-linus' of ↵Konrad Rzeszutek Wilk2012-09-263-1/+2
|\ \ \ \ \ \ | |_|_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://xenbits.xen.org/people/sstabellini/linux-pvhvm into stable/for-linus-3.7 * 'xenarm-for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm: arm: introduce a DTS for Xen unprivileged virtual machines MAINTAINERS: add myself as Xen ARM maintainer xen/arm: compile netback xen/arm: compile blkfront and blkback xen/arm: implement alloc/free_xenballooned_pages with alloc_pages/kfree xen/arm: receive Xen events on ARM xen/arm: initialize grant_table on ARM xen/arm: get privilege status xen/arm: introduce CONFIG_XEN on ARM xen: do not compile manage, balloon, pci, acpi, pcpu and cpu_hotplug on ARM xen/arm: Introduce xen_ulong_t for unsigned long xen/arm: Xen detection and shared_info page mapping docs: Xen ARM DT bindings xen/arm: empty implementation of grant_table arch specific functions xen/arm: sync_bitops xen/arm: page.h definitions xen/arm: hypercalls arm: initial Xen support Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | xen/arm: receive Xen events on ARMStefano Stabellini2012-09-143-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compile events.c on ARM. Parse, map and enable the IRQ to get event notifications from the device tree (node "/xen"). Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | xen/vga: add the xen EFI video mode supportJan Beulich2012-09-241-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to add xen EFI frambebuffer video support, it is required to add xen-efi's new video type (XEN_VGATYPE_EFI_LFB) case and handle it in the function xen_init_vga and set the video type to VIDEO_TYPE_EFI to enable efi video mode. The original patch from which this was broken out from: http://marc.info/?i=4E099AA6020000780004A4C6@nat28.tlf.novell.com Signed-off-by: Jan Beulich <JBeulich@novell.com> Signed-off-by: Tang Liang <liang.tang@oracle.com> [v2: The original author is Jan Beulich and Liang Tang ported it to upstream] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | xen/x86: retrieve keyboard shift status flags from hypervisor.Konrad Rzeszutek Wilk2012-09-241-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The xen c/s 25873 allows the hypervisor to retrieve the NUMLOCK flag. With this patch, the Linux kernel can get the state according to the data in the BIOS. Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | Merge branch 'stable/late-swiotlb.v3.3' into stable/for-linus-3.7Konrad Rzeszutek Wilk2012-09-231-5/+42
|\ \ \ \ \ \ | |/ / / / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * stable/late-swiotlb.v3.3: xen/swiotlb: Fix compile warnings when using plain integer instead of NULL pointer. xen/swiotlb: Remove functions not needed anymore. xen/pcifront: Use Xen-SWIOTLB when initting if required. xen/swiotlb: For early initialization, return zero on success. xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used. xen/swiotlb: Move the error strings to its own function. xen/swiotlb: Move the nr_tbl determination in its own function. swiotlb: add the late swiotlb initialization function with iotlb memory xen/swiotlb: With more than 4GB on 64-bit, disable the native SWIOTLB. xen/swiotlb: Simplify the logic. Conflicts: arch/x86/xen/pci-swiotlb-xen.c Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | xen/swiotlb: Fix compile warnings when using plain integer instead of NULL ↵Konrad Rzeszutek Wilk2012-09-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pointer. arch/x86/xen/pci-swiotlb-xen.c:96:1: warning: Using plain integer as NULL pointer arch/x86/xen/pci-swiotlb-xen.c:96:1: warning: Using plain integer as NULL pointer Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late ↵Konrad Rzeszutek Wilk2012-09-171-2/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | when PV PCI is used. With this patch we provide the functionality to initialize the Xen-SWIOTLB late in the bootup cycle - specifically for Xen PCI-frontend. We still will work if the user had supplied 'iommu=soft' on the Linux command line. Note: We cannot depend on after_bootmem to automatically determine whether this is early or not. This is because when PCI IOMMUs are initialized it is after after_bootmem but before a lot of "other" subsystems are initialized. CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> [v1: Fix smatch warnings] [v2: Added check for xen_swiotlb] [v3: Rebased with new xen-swiotlb changes] [v4: squashed xen/swiotlb: Depending on after_bootmem is not correct in] Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | xen/swiotlb: With more than 4GB on 64-bit, disable the native SWIOTLB.Konrad Rzeszutek Wilk2012-08-211-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a PV guest is booted the native SWIOTLB should not be turned on. It does not help us (we don't have any PCI devices) and it eats 64MB of good memory. In the case of PV guests with PCI devices we need the Xen-SWIOTLB one. [v1: Rewrite comment per Stefano's suggestion] Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | xen/swiotlb: Simplify the logic.Konrad Rzeszutek Wilk2012-08-211-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Its pretty easy: 1). We only check to see if we need Xen SWIOTLB for PV guests. 2). If swiotlb=force or iommu=soft is set, then Xen SWIOTLB will be enabled. 3). If it is an initial domain, then Xen SWIOTLB will be enabled. 4). Native SWIOTLB must be disabled for PV guests. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* | | | | | Merge branch 'stable/128gb.v5.1' into stable/for-linus-3.7Konrad Rzeszutek Wilk2012-09-125-47/+254
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * stable/128gb.v5.1: xen/mmu: If the revector fails, don't attempt to revector anything else. xen/p2m: When revectoring deal with holes in the P2M array. xen/mmu: Release just the MFN list, not MFN list and part of pagetables. xen/mmu: Remove from __ka space PMD entries for pagetables. xen/mmu: Copy and revector the P2M tree. xen/p2m: Add logic to revector a P2M tree to use __va leafs. xen/mmu: Recycle the Xen provided L4, L3, and L2 pages xen/mmu: For 64-bit do not call xen_map_identity_early xen/mmu: use copy_page instead of memcpy. xen/mmu: Provide comments describing the _ka and _va aliasing issue xen/mmu: The xen_setup_kernel_pagetable doesn't need to return anything. Revert "xen/x86: Workaround 64-bit hypervisor and 32-bit initial domain." and "xen/x86: Use memblock_reserve for sensitive areas." xen/x86: Workaround 64-bit hypervisor and 32-bit initial domain. xen/x86: Use memblock_reserve for sensitive areas. xen/p2m: Fix the comment describing the P2M tree. Conflicts: arch/x86/xen/mmu.c The pagetable_init is the old xen_pagetable_setup_done and xen_pagetable_setup_start rolled in one. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/mmu: If the revector fails, don't attempt to revector anything else.Konrad Rzeszutek Wilk2012-08-231-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the P2M revectoring would fail, we would try to continue on by cleaning the PMD for L1 (PTE) page-tables. The xen_cleanhighmap is greedy and erases the PMD on both boundaries. Since the P2M array can share the PMD, we would wipe out part of the __ka that is still used in the P2M tree to point to P2M leafs. This fixes it by bypassing the revectoring and continuing on. If the revector fails, a nice WARN is printed so we can still troubleshoot this. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/p2m: When revectoring deal with holes in the P2M array.Konrad Rzeszutek Wilk2012-08-231-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we free the PFNs and then subsequently populate them back during bootup: Freeing 20000-20200 pfn range: 512 pages freed 1-1 mapping on 20000->20200 Freeing 40000-40200 pfn range: 512 pages freed 1-1 mapping on 40000->40200 Freeing bad80-badf4 pfn range: 116 pages freed 1-1 mapping on bad80->badf4 Freeing badf6-bae7f pfn range: 137 pages freed 1-1 mapping on badf6->bae7f Freeing bb000-100000 pfn range: 282624 pages freed 1-1 mapping on bb000->100000 Released 283999 pages of unused memory Set 283999 page(s) to 1-1 mapping Populating 1acb8a-1f20e9 pfn range: 283999 pages added We end up having the P2M array (that is the one that was grafted on the P2M tree) filled with IDENTITY_FRAME or INVALID_P2M_ENTRY) entries. The patch titled "xen/p2m: Reuse existing P2M leafs if they are filled with 1:1 PFNs or INVALID." recycles said slots and replaces the P2M tree leaf's with &mfn_list[xx] with p2m_identity or p2m_missing. And re-uses the P2M array sections for other P2M tree leaf's. For the above mentioned bootup excerpt, the PFNs at 0x20000->0x20200 are going to be IDENTITY based: P2M[0][256][0] -> P2M[0][257][0] get turned in IDENTITY_FRAME. We can re-use that and replace P2M[0][256] to point to p2m_identity. The "old" page (the grafted P2M array provided by Xen) that was at P2M[0][256] gets put somewhere else. Specifically at P2M[6][358], b/c when we populate back: Populating 1acb8a-1f20e9 pfn range: 283999 pages added we fill P2M[6][358][0] (and P2M[6][358], P2M[6][359], ...) with the new MFNs. That is all OK, except when we revector we assume that the PFN count would be the same in the grafted P2M array and in the newly allocated. Since that is no longer the case, as we have holes in the P2M that point to p2m_missing or p2m_identity we have to take that into account. [v2: Check for overflow] [v3: Move within the __va check] [v4: Fix the computation] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/mmu: Release just the MFN list, not MFN list and part of pagetables.Konrad Rzeszutek Wilk2012-08-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We call memblock_reserve for [start of mfn list] -> [PMD aligned end of mfn list] instead of <start of mfn list> -> <page aligned end of mfn list]. This has the disastrous effect that if at bootup the end of mfn_list is not PMD aligned we end up returning to memblock parts of the region past the mfn_list array. And those parts are the PTE tables with the disastrous effect of seeing this at bootup: Write protecting the kernel read-only data: 10240k Freeing unused kernel memory: 1860k freed Freeing unused kernel memory: 200k freed (XEN) mm.c:2429:d0 Bad type (saw 1400000000000002 != exp 7000000000000000) for mfn 116a80 (pfn 14e26) ... (XEN) mm.c:908:d0 Error getting mfn 116a83 (pfn 14e2a) from L1 entry 8000000116a83067 for l1e_owner=0, pg_owner=0 (XEN) mm.c:908:d0 Error getting mfn 4040 (pfn 5555555555555555) from L1 entry 0000000004040601 for l1e_owner=0, pg_owner=0 .. and so on. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/mmu: Remove from __ka space PMD entries for pagetables.Konrad Rzeszutek Wilk2012-08-231-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Please first read the description in "xen/mmu: Copy and revector the P2M tree." At this stage, the __ka address space (which is what the old P2M tree was using) is partially disassembled. The cleanup_highmap has removed the PMD entries from 0-16MB and anything past _brk_end up to the max_pfn_mapped (which is the end of the ramdisk). The xen_remove_p2m_tree and code around has ripped out the __ka for the old P2M array. Here we continue on doing it to where the Xen page-tables were. It is safe to do it, as the page-tables are addressed using __va. For good measure we delete anything that is within MODULES_VADDR and up to the end of the PMD. At this point the __ka only contains PMD entries for the start of the kernel up to __brk. [v1: Per Stefano's suggestion wrapped the MODULES_VADDR in debug] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/mmu: Copy and revector the P2M tree.Konrad Rzeszutek Wilk2012-08-231-0/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Please first read the description in "xen/p2m: Add logic to revector a P2M tree to use __va leafs" patch. The 'xen_revector_p2m_tree()' function allocates a new P2M tree copies the contents of the old one in it, and returns the new one. At this stage, the __ka address space (which is what the old P2M tree was using) is partially disassembled. The cleanup_highmap has removed the PMD entries from 0-16MB and anything past _brk_end up to the max_pfn_mapped (which is the end of the ramdisk). We have revectored the P2M tree (and the one for save/restore as well) to use new shiny __va address to new MFNs. The xen_start_info has been taken care of already in 'xen_setup_kernel_pagetable()' and xen_start_info->shared_info in 'xen_setup_shared_info()', so we are free to roam and delete PMD entries - which is exactly what we are going to do. We rip out the __ka for the old P2M array. [v1: Fix smatch warnings] [v2: memset was doing 0 instead of 0xff] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/p2m: Add logic to revector a P2M tree to use __va leafs.Konrad Rzeszutek Wilk2012-08-232-0/+71
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During bootup Xen supplies us with a P2M array. It sticks it right after the ramdisk, as can be seen with a 128GB PV guest: (certain parts removed for clarity): xc_dom_build_image: called xc_dom_alloc_segment: kernel : 0xffffffff81000000 -> 0xffffffff81e43000 (pfn 0x1000 + 0xe43 pages) xc_dom_pfn_to_ptr: domU mapping: pfn 0x1000+0xe43 at 0x7f097d8bf000 xc_dom_alloc_segment: ramdisk : 0xffffffff81e43000 -> 0xffffffff925c7000 (pfn 0x1e43 + 0x10784 pages) xc_dom_pfn_to_ptr: domU mapping: pfn 0x1e43+0x10784 at 0x7f0952dd2000 xc_dom_alloc_segment: phys2mach : 0xffffffff925c7000 -> 0xffffffffa25c7000 (pfn 0x125c7 + 0x10000 pages) xc_dom_pfn_to_ptr: domU mapping: pfn 0x125c7+0x10000 at 0x7f0942dd2000 xc_dom_alloc_page : start info : 0xffffffffa25c7000 (pfn 0x225c7) xc_dom_alloc_page : xenstore : 0xffffffffa25c8000 (pfn 0x225c8) xc_dom_alloc_page : console : 0xffffffffa25c9000 (pfn 0x225c9) nr_page_tables: 0x0000ffffffffffff/48: 0xffff000000000000 -> 0xffffffffffffffff, 1 table(s) nr_page_tables: 0x0000007fffffffff/39: 0xffffff8000000000 -> 0xffffffffffffffff, 1 table(s) nr_page_tables: 0x000000003fffffff/30: 0xffffffff80000000 -> 0xffffffffbfffffff, 1 table(s) nr_page_tables: 0x00000000001fffff/21: 0xffffffff80000000 -> 0xffffffffa27fffff, 276 table(s) xc_dom_alloc_segment: page tables : 0xffffffffa25ca000 -> 0xffffffffa26e1000 (pfn 0x225ca + 0x117 pages) xc_dom_pfn_to_ptr: domU mapping: pfn 0x225ca+0x117 at 0x7f097d7a8000 xc_dom_alloc_page : boot stack : 0xffffffffa26e1000 (pfn 0x226e1) xc_dom_build_image : virt_alloc_end : 0xffffffffa26e2000 xc_dom_build_image : virt_pgtab_end : 0xffffffffa2800000 So the physical memory and virtual (using __START_KERNEL_map addresses) layout looks as so: phys __ka /------------\ /-------------------\ | 0 | empty | 0xffffffff80000000| | .. | | .. | | 16MB | <= kernel starts | 0xffffffff81000000| | .. | | | | 30MB | <= kernel ends => | 0xffffffff81e43000| | .. | & ramdisk starts | .. | | 293MB | <= ramdisk ends=> | 0xffffffff925c7000| | .. | & P2M starts | .. | | .. | | .. | | 549MB | <= P2M ends => | 0xffffffffa25c7000| | .. | start_info | 0xffffffffa25c7000| | .. | xenstore | 0xffffffffa25c8000| | .. | cosole | 0xffffffffa25c9000| | 549MB | <= page tables => | 0xffffffffa25ca000| | .. | | | | 550MB | <= PGT end => | 0xffffffffa26e1000| | .. | boot stack | | \------------/ \-------------------/ As can be seen, the ramdisk, P2M and pagetables are taking a bit of __ka addresses space. Which is a problem since the MODULES_VADDR starts at 0xffffffffa0000000 - and P2M sits right in there! This results during bootup with the inability to load modules, with this error: ------------[ cut here ]------------ WARNING: at /home/konrad/ssd/linux/mm/vmalloc.c:106 vmap_page_range_noflush+0x2d9/0x370() Call Trace: [<ffffffff810719fa>] warn_slowpath_common+0x7a/0xb0 [<ffffffff81030279>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e [<ffffffff81071a45>] warn_slowpath_null+0x15/0x20 [<ffffffff81130b89>] vmap_page_range_noflush+0x2d9/0x370 [<ffffffff81130c4d>] map_vm_area+0x2d/0x50 [<ffffffff811326d0>] __vmalloc_node_range+0x160/0x250 [<ffffffff810c5369>] ? module_alloc_update_bounds+0x19/0x80 [<ffffffff810c6186>] ? load_module+0x66/0x19c0 [<ffffffff8105cadc>] module_alloc+0x5c/0x60 [<ffffffff810c5369>] ? module_alloc_update_bounds+0x19/0x80 [<ffffffff810c5369>] module_alloc_update_bounds+0x19/0x80 [<ffffffff810c70c3>] load_module+0xfa3/0x19c0 [<ffffffff812491f6>] ? security_file_permission+0x86/0x90 [<ffffffff810c7b3a>] sys_init_module+0x5a/0x220 [<ffffffff815ce339>] system_call_fastpath+0x16/0x1b ---[ end trace fd8f7704fdea0291 ]--- vmalloc: allocation failure, allocated 16384 of 20480 bytes modprobe: page allocation failure: order:0, mode:0xd2 Since the __va and __ka are 1:1 up to MODULES_VADDR and cleanup_highmap rids __ka of the ramdisk mapping, what we want to do is similar - get rid of the P2M in the __ka address space. There are two ways of fixing this: 1) All P2M lookups instead of using the __ka address would use the __va address. This means we can safely erase from __ka space the PMD pointers that point to the PFNs for P2M array and be OK. 2). Allocate a new array, copy the existing P2M into it, revector the P2M tree to use that, and return the old P2M to the memory allocate. This has the advantage that it sets the stage for using XEN_ELF_NOTE_INIT_P2M feature. That feature allows us to set the exact virtual address space we want for the P2M - and allows us to boot as initial domain on large machines. So we pick option 2). This patch only lays the groundwork in the P2M code. The patch that modifies the MMU is called "xen/mmu: Copy and revector the P2M tree." Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/mmu: Recycle the Xen provided L4, L3, and L2 pagesKonrad Rzeszutek Wilk2012-08-231-7/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As we are not using them. We end up only using the L1 pagetables and grafting those to our page-tables. [v1: Per Stefano's suggestion squashed two commits] [v2: Per Stefano's suggestion simplified loop] [v3: Fix smatch warnings] [v4: Add more comments] Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/mmu: For 64-bit do not call xen_map_identity_earlyKonrad Rzeszutek Wilk2012-08-231-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | B/c we do not need it. During the startup the Xen provides us with all the initial memory mapped that we need to function. The initial memory mapped is up to the bootstack, which means we can reference using __ka up to 4.f): (from xen/interface/xen.h): 4. This the order of bootstrap elements in the initial virtual region: a. relocated kernel image b. initial ram disk [mod_start, mod_len] c. list of allocated page frames [mfn_list, nr_pages] d. start_info_t structure [register ESI (x86)] e. bootstrap page tables [pt_base, CR3 (x86)] f. bootstrap stack [register ESP (x86)] (initial ram disk may be ommitted). [v1: More comments in git commit] Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/mmu: use copy_page instead of memcpy.Konrad Rzeszutek Wilk2012-08-231-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After all, this is what it is there for. Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * | | | | | xen/mmu: Provide comments describing the _ka and _va aliasing issueKonrad Rzeszutek Wilk2012-08-231-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Which is that the level2_kernel_pgt (__ka virtual addresses) and level2_ident_pgt (__va virtual address) contain the same PMD entries. So if you modify a PTE in __ka, it will be reflected in __va (and vice-versa). Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>