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2012-11-17xen/mmu: Use Xen specific TLB flush instead of the generic one.Konrad Rzeszutek Wilk
commit 95a7d76897c1e7243d4137037c66d15cbf2cce76 upstream. 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 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-07xen/pte: Fix crashes when trying to see non-existent PGD/PMD/PUD/PTEsKonrad Rzeszutek Wilk
If I try to do "cat /sys/kernel/debug/kernel_page_tables" I end up with: BUG: unable to handle kernel paging request at ffffc7fffffff000 IP: [<ffffffff8106aa51>] ptdump_show+0x221/0x480 PGD 0 Oops: 0000 [#1] SMP CPU 0 .. snip.. RAX: 0000000000000000 RBX: ffffc00000000fff RCX: 0000000000000000 RDX: 0000800000000000 RSI: 0000000000000000 RDI: ffffc7fffffff000 which is due to the fact we are trying to access a PFN that is not accessible to us. The reason (at least in this case) was that PGD[256] is set to __HYPERVISOR_VIRT_START which was setup (by the hypervisor) to point to a read-only linear map of the MFN->PFN array. During our parsing we would get the MFN (a valid one), try to look it up in the MFN->PFN tree and find it invalid and return ~0 as PFN. Then pte_mfn_to_pfn would happilly feed that in, attach the flags and return it back to the caller. 'ptdump_show' bitshifts it and gets and invalid value that it tries to dereference. Instead of doing all of that, we detect the ~0 case and just return !_PAGE_PRESENT. This bug has been in existence .. at least until 2.6.37 (yikes!) CC: stable@kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-04-06Merge tag 'stable/for-linus-3.4-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull xen fixes from Konrad Rzeszutek Wilk: "Two fixes for regressions: * one is a workaround that will be removed in v3.5 with proper fix in the tip/x86 tree, * the other is to fix drivers to load on PV (a previous patch made them only load in PVonHVM mode). The rest are just minor fixes in the various drivers and some cleanup in the core code." * tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pcifront: avoid pci_frontend_enable_msix() falsely returning success xen/pciback: fix XEN_PCI_OP_enable_msix result xen/smp: Remove unnecessary call to smp_processor_id() xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus io-apic entries' xen: only check xen_platform_pci_unplug if hvm
2012-04-06xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus ↵Konrad Rzeszutek Wilk
io-apic entries' The above mentioned patch checks the IOAPIC and if it contains -1, then it unmaps said IOAPIC. But under Xen we get this: BUG: unable to handle kernel NULL pointer dereference at 0000000000000040 IP: [<ffffffff8134e51f>] xen_irq_init+0x1f/0xb0 PGD 0 Oops: 0002 [#1] SMP CPU 0 Modules linked in: Pid: 1, comm: swapper/0 Not tainted 3.2.10-3.fc16.x86_64 #1 Dell Inc. Inspiron 1525 /0U990C RIP: e030:[<ffffffff8134e51f>] [<ffffffff8134e51f>] xen_irq_init+0x1f/0xb0 RSP: e02b: ffff8800d42cbb70 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 00000000ffffffef RCX: 0000000000000001 RDX: 0000000000000040 RSI: 00000000ffffffef RDI: 0000000000000001 RBP: ffff8800d42cbb80 R08: ffff8800d6400000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffef R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000010 FS: 0000000000000000(0000) GS:ffff8800df5fe000(0000) knlGS:0000000000000000 CS: e033 DS: 0000 ES: 0000 CR0:000000008005003b CR2: 0000000000000040 CR3: 0000000001a05000 CR4: 0000000000002660 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process swapper/0 (pid: 1, threadinfo ffff8800d42ca000, task ffff8800d42d0000) Stack: 00000000ffffffef 0000000000000010 ffff8800d42cbbe0 ffffffff8134f157 ffffffff8100a9b2 ffffffff8182ffd1 00000000000000a0 00000000829e7384 0000000000000002 0000000000000010 00000000ffffffff 0000000000000000 Call Trace: [<ffffffff8134f157>] xen_bind_pirq_gsi_to_irq+0x87/0x230 [<ffffffff8100a9b2>] ? check_events+0x12+0x20 [<ffffffff814bab42>] xen_register_pirq+0x82/0xe0 [<ffffffff814bac1a>] xen_register_gsi.part.2+0x4a/0xd0 [<ffffffff814bacc0>] acpi_register_gsi_xen+0x20/0x30 [<ffffffff8103036f>] acpi_register_gsi+0xf/0x20 [<ffffffff8131abdb>] acpi_pci_irq_enable+0x12e/0x202 [<ffffffff814bc849>] pcibios_enable_device+0x39/0x40 [<ffffffff812dc7ab>] do_pci_enable_device+0x4b/0x70 [<ffffffff812dc878>] __pci_enable_device_flags+0xa8/0xf0 [<ffffffff812dc8d3>] pci_enable_device+0x13/0x20 The reason we are dying is b/c the call acpi_get_override_irq() is used, which returns the polarity and trigger for the IRQs. That function calls mp_find_ioapics to get the 'struct ioapic' structure - which along with the mp_irq[x] is used to figure out the default values and the polarity/trigger overrides. Since the mp_find_ioapics now returns -1 [b/c the IOAPIC is filled with 0xffffffff], the acpi_get_override_irq() stops trying to lookup in the mp_irq[x] the proper INT_SRV_OVR and we can't install the SCI interrupt. The proper fix for this is going in v3.5 and adds an x86_io_apic_ops struct so that platforms can override it. But for v3.4 lets carry this work-around. This patch does that by providing a slightly different variant of the fake IOAPIC entries. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-22Merge tag 'stable/for-linus-3.4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull xen updates from Konrad Rzeszutek Wilk: "which has three neat features: - PV multiconsole support, so that there can be hvc1, hvc2, etc; This can be used in HVM and in PV mode. - P-state and C-state power management driver that uploads said power management data to the hypervisor. It also inhibits cpufreq scaling drivers to load so that only the hypervisor can make power management decisions - fixing a weird perf bug. There is one thing in the Kconfig that you won't like: "default y if (X86_ACPI_CPUFREQ = y || X86_POWERNOW_K8 = y)" (note, that it all depends on CONFIG_XEN which depends on CONFIG_PARAVIRT which by default is off). I've a fix to convert that boolean expression into "default m" which I am going to post after the cpufreq git pull - as the two patches to make this work depend on a fix in Dave Jones's tree. - Function Level Reset (FLR) support in the Xen PCI backend. Fixes: - Kconfig dependencies for Xen PV keyboard and video - Compile warnings and constify fixes - Change over to use percpu_xxx instead of this_cpu_xxx" Fix up trivial conflicts in drivers/tty/hvc/hvc_xen.c due to changes to a removed commit. * tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen kconfig: relax INPUT_XEN_KBDDEV_FRONTEND deps xen/acpi-processor: C and P-state driver that uploads said data to hypervisor. xen: constify all instances of "struct attribute_group" xen/xenbus: ignore console/0 hvc_xen: introduce HVC_XEN_FRONTEND hvc_xen: implement multiconsole support hvc_xen: support PV on HVM consoles xenbus: don't free other end details too early xen/enlighten: Expose MWAIT and MWAIT_LEAF if hypervisor OKs it. xen/setup/pm/acpi: Remove the call to boot_option_idle_override. xenbus: address compiler warnings xen: use this_cpu_xxx replace percpu_xxx funcs xen/pciback: Support pci_reset_function, aka FLR or D3 support. pci: Introduce __pci_reset_function_locked to be used when holding device_lock. xen: Utilize the restore_msi_irqs hook.
2012-02-20xen/pat: Disable PAT support for now.Konrad Rzeszutek Wilk
[Pls also look at https://lkml.org/lkml/2012/2/10/228] Using of PAT to change pages from WB to WC works quite nicely. Changing it back to WB - not so much. The crux of the matter is that the code that does this (__page_change_att_set_clr) has only limited information so when it tries to the change it gets the "raw" unfiltered information instead of the properly filtered one - and the "raw" one tell it that PSE bit is on (while infact it is not). As a result when the PTE is set to be WB from WC, we get tons of: :WARNING: at arch/x86/xen/mmu.c:475 xen_make_pte+0x67/0xa0() :Hardware name: HP xw4400 Workstation .. snip.. :Pid: 27, comm: kswapd0 Tainted: G W 3.2.2-1.fc16.x86_64 #1 :Call Trace: : [<ffffffff8106dd1f>] warn_slowpath_common+0x7f/0xc0 : [<ffffffff8106dd7a>] warn_slowpath_null+0x1a/0x20 : [<ffffffff81005a17>] xen_make_pte+0x67/0xa0 : [<ffffffff810051bd>] __raw_callee_save_xen_make_pte+0x11/0x1e : [<ffffffff81040e15>] ? __change_page_attr_set_clr+0x9d5/0xc00 : [<ffffffff8114c2e8>] ? __purge_vmap_area_lazy+0x158/0x1d0 : [<ffffffff8114cca5>] ? vm_unmap_aliases+0x175/0x190 : [<ffffffff81041168>] change_page_attr_set_clr+0x128/0x4c0 : [<ffffffff81041542>] set_pages_array_wb+0x42/0xa0 : [<ffffffff8100a9b2>] ? check_events+0x12/0x20 : [<ffffffffa0074d4c>] ttm_pages_put+0x1c/0x70 [ttm] : [<ffffffffa0074e98>] ttm_page_pool_free+0xf8/0x180 [ttm] : [<ffffffffa0074f78>] ttm_pool_mm_shrink+0x58/0x90 [ttm] : [<ffffffff8112ba04>] shrink_slab+0x154/0x310 : [<ffffffff8112f17a>] balance_pgdat+0x4fa/0x6c0 : [<ffffffff8112f4b8>] kswapd+0x178/0x3d0 : [<ffffffff815df134>] ? __schedule+0x3d4/0x8c0 : [<ffffffff81090410>] ? remove_wait_queue+0x50/0x50 : [<ffffffff8112f340>] ? balance_pgdat+0x6c0/0x6c0 : [<ffffffff8108fb6c>] kthread+0x8c/0xa0 for every page. The proper fix for this is has been posted and is https://lkml.org/lkml/2012/2/10/228 "x86/cpa: Use pte_attrs instead of pte_flags on CPA/set_p.._wb/wc operations." along with a detailed description of the problem and solution. But since that posting has gone nowhere I am proposing this band-aid solution so that at least users don't get the page corruption (the pages that are WC don't get changed to WB and end up being recycled for filesystem or other things causing mysterious crashes). The negative impact of this patch is that users of WC flag (which are InfiniBand, radeon, nouveau drivers) won't be able to set that flag - so they are going to see performance degradation. But stability is more important here. Fixes RH BZ# 742032, 787403, and 745574 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-24xen: use this_cpu_xxx replace percpu_xxx funcsAlex Shi
percpu_xxx funcs are duplicated with this_cpu_xxx funcs, so replace them for further code clean up. I don't know much of xen code. But, since the code is in x86 architecture, the percpu_xxx is exactly same as this_cpu_xxx serials functions. So, the change is safe. Signed-off-by: Alex Shi <alex.shi@intel.com> Acked-by: Christoph Lameter <cl@gentwo.org> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-01-09xen/mmu: Fix compile errors introduced by x86/memblock mismerge.Konrad Rzeszutek Wilk
The git commit d4bbf7e7759afc172e2bfbc5c416324590049cdd "Merge branch 'master' into x86/memblock" mismerged the 32-bit section causing: arch/x86/xen/mmu.c: In function ‘xen_setup_kernel_pagetable’: arch/x86/xen/mmu.c:1855: error: expected ‘;’ before ‘)’ token arch/x86/xen/mmu.c:1855: error: expected statement before ‘)’ token Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-11-28Merge branch 'master' into x86/memblockTejun Heo
Conflicts & resolutions: * arch/x86/xen/setup.c dc91c728fd "xen: allow extra memory to be in multiple regions" 24aa07882b "memblock, x86: Replace memblock_x86_reserve/free..." conflicted on xen_add_extra_mem() updates. The resolution is trivial as the latter just want to replace memblock_x86_reserve_range() with memblock_reserve(). * drivers/pci/intel-iommu.c 166e9278a3f "x86/ia64: intel-iommu: move to drivers/iommu/" 5dfe8660a3d "bootmem: Replace work_with_active_regions() with..." conflicted as the former moved the file under drivers/iommu/. Resolved by applying the chnages from the latter on the moved file. * mm/Kconfig 6661672053a "memblock: add NO_BOOTMEM config symbol" c378ddd53f9 "memblock, x86: Make ARCH_DISCARD_MEMBLOCK a config option" conflicted trivially. Both added config options. Just letting both add their own options resolves the conflict. * mm/memblock.c d1f0ece6cdc "mm/memblock.c: small function definition fixes" ed7b56a799c "memblock: Remove memblock_memory_can_coalesce()" confliected. The former updates function removed by the latter. Resolution is trivial. Signed-off-by: Tejun Heo <tj@kernel.org>
2011-10-25Merge branches 'stable/bug.fixes-3.2' and 'stable/mmu.fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/bug.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/p2m/debugfs: Make type_name more obvious. xen/p2m/debugfs: Fix potential pointer exception. xen/enlighten: Fix compile warnings and set cx to known value. xen/xenbus: Remove the unnecessary check. xen/irq: If we fail during msi_capability_init return proper error code. xen/events: Don't check the info for NULL as it is already done. xen/events: BUG() when we can't allocate our event->irq array. * 'stable/mmu.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: Fix selfballooning and ensure it doesn't go too far xen/gntdev: Fix sleep-inside-spinlock xen: modify kernel mappings corresponding to granted pages xen: add an "highmem" parameter to alloc_xenballooned_pages xen/p2m: Use SetPagePrivate and its friends for M2P overrides. xen/p2m: Make debug/xen/mmu/p2m visible again. Revert "xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set."
2011-09-23xen/p2m: Make debug/xen/mmu/p2m visible again.Konrad Rzeszutek Wilk
We dropped a lot of the MMU debugfs in favour of using tracing API - but there is one which just provides mostly static information that was made invisible by this change. Bring it back. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-09-16Merge branch 'stable/bug.fixes' of git://oss.oracle.com/git/kwilk/xenLinus Torvalds
* 'stable/bug.fixes' of git://oss.oracle.com/git/kwilk/xen: xen/i386: follow-up to "replace order-based range checking of M2P table by linear one" xen/irq: Alter the locking to use a mutex instead of a spinlock. xen/e820: if there is no dom0_mem=, don't tweak extra_pages. xen: disable PV spinlocks on HVM
2011-09-15xen/i386: follow-up to "replace order-based range checking of M2P table by ↵Jan Beulich
linear one" The numbers obtained from the hypervisor really can't ever lead to an overflow here, only the original calculation going through the order of the range could have. This avoids the (as Jeremy points outs) somewhat ugly NULL-based calculation here. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-08-22Merge branch 'stable/bug.fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/bug.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/tracing: Fix tracing config option properly xen: Do not enable PV IPIs when vector callback not present xen/x86: replace order-based range checking of M2P table by linear one xen: xen-selfballoon.c needs more header files
2011-08-17xen/x86: replace order-based range checking of M2P table by linear oneJan Beulich
The order-based approach is not only less efficient (requiring a shift and a compare, typical generated code looking like this mov eax, [machine_to_phys_order] mov ecx, eax shr ebx, cl test ebx, ebx jnz ... whereas a direct check requires just a compare, like in cmp ebx, [machine_to_phys_nr] jae ... ), but also slightly dangerous in the 32-on-64 case - the element address calculation can wrap if the next power of two boundary is sufficiently far away from the actual upper limit of the table, and hence can result in user space addresses being accessed (with it being unknown what may actually be mapped there). Additionally, the elimination of the mistaken use of fls() here (should have been __fls()) fixes a latent issue on x86-64 that would trigger if the code was run on a system with memory extending beyond the 44-bit boundary. CC: stable@kernel.org Signed-off-by: Jan Beulich <jbeulich@novell.com> [v1: Based on Jeremy's feedback] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-08-12Merge branch 'x86-vdso-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip: x86-64: Rework vsyscall emulation and add vsyscall= parameter x86-64: Wire up getcpu syscall x86: Remove unnecessary compile flag tweaks for vsyscall code x86-64: Add vsyscall:emulate_vsyscall trace event x86-64: Add user_64bit_mode paravirt op x86-64, xen: Enable the vvar mapping x86-64: Work around gold bug 13023 x86-64: Move the "user" vsyscall segment out of the data segment. x86-64: Pad vDSO to a page boundary
2011-08-09Revert "xen/debug: WARN_ON when identity PFN has no _PAGE_IOMAP flag set."Konrad Rzeszutek Wilk
We don' use it anymore and there are more false positives. This reverts commit fc25151d9ac7d809239fe68de0a1490b504bb94a. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-08-04x86-64, xen: Enable the vvar mappingAndy Lutomirski
Xen needs to handle VVAR_PAGE, introduced in git commit: 9fd67b4ed0714ab718f1f9bd14c344af336a6df7 x86-64: Give vvars their own page Otherwise we die during bootup with a message like: (XEN) mm.c:940:d10 Error getting mfn 1888 (pfn 1e3e48) from L1 entry 8000000001888465 for l1e_owner=10, pg_owner=10 (XEN) mm.c:5049:d10 ptwr_emulate: could not get_page_from_l1e() [ 0.000000] BUG: unable to handle kernel NULL pointer dereference at (null) [ 0.000000] IP: [<ffffffff8103a930>] xen_set_pte+0x20/0xe0 Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/4659478ed2f3480938f96491c2ecbe2b2e113a23.1312378163.git.luto@mit.edu Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-18xen/mmu: tune pgtable alloc/releaseJeremy Fitzhardinge
Make sure the fastpath code is inlined. Batch the page permission change and the pin/unpin, and make sure that it can be batched with any adjacent set_pte/pmd/etc operations. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18xen/mmu: use extend_args for more mmuext updatesJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18xen/trace: add tlb flush tracepointsJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18xen/trace: add xen_pgd_(un)pin tracepointsJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18xen/trace: add ptpage alloc/release tracepointsJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-18xen/trace: add mmu tracepointsJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-14memblock, x86: Replace memblock_x86_reserve/free_range() with generic onesTejun Heo
Other than sanity check and debug message, the x86 specific version of memblock reserve/free functions are simple wrappers around the generic versions - memblock_reserve/free(). This patch adds debug messages with caller identification to the generic versions and replaces x86 specific ones and kills them. arch/x86/include/asm/memblock.h and arch/x86/mm/memblock.c are empty after this change and removed. Signed-off-by: Tejun Heo <tj@kernel.org> Link: http://lkml.kernel.org/r/1310462166-31469-14-git-send-email-tj@kernel.org Cc: Yinghai Lu <yinghai@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-06-30xen/mmu: Fix for linker errors when CONFIG_SMP is not defined.Konrad Rzeszutek Wilk
Simple enough - we use an extern defined symbol which is not defined when CONFIG_SMP is not defined. This fixes the linker dying. CC: stable@kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-06-15xen: support CONFIG_MAXSMPAndrew Jones
The MAXSMP config option requires CPUMASK_OFFSTACK, which in turn requires we init the memory for the maps while we bring up the cpus. MAXSMP also increases NR_CPUS to 4096. This increase in size exposed an issue in the argument construction for multicalls from xen_flush_tlb_others. The args should only need space for the actual number of cpus. Also in 2.6.39 it exposes a bootup problem. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff8157a1d3>] set_cpu_sibling_map+0x123/0x30d ... Call Trace: [<ffffffff81039a3f>] ? xen_restore_fl_direct_reloc+0x4/0x4 [<ffffffff819dc4db>] xen_smp_prepare_cpus+0x36/0x135 .. CC: stable@kernel.org Signed-off-by: Andrew Jones <drjones@redhat.com> [v2: Updated to compile on 3.0] [v3: Updated to compile when CONFIG_SMP is not defined] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-06-09xen: partially revert "xen: set max_pfn_mapped to the last pfn mapped"Stefano Stabellini
We only need to set max_pfn_mapped to the last pfn mapped on x86_64 to make sure that cleanup_highmap doesn't remove important mappings at _end. We don't need to do this on x86_32 because cleanup_highmap is not called on x86_32. Besides lowering max_pfn_mapped on x86_32 has the unwanted side effect of limiting the amount of memory available for the 1:1 kernel pagetable allocation. This patch reverts the x86_32 part of the original patch. CC: stable@kernel.org Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-26Merge branch 'upstream/tidy-xen-mmu-2.6.39' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen * 'upstream/tidy-xen-mmu-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: xen: fix compile without CONFIG_XEN_DEBUG_FS Use arbitrary_virt_to_machine() to deal with ioremapped pud updates. Use arbitrary_virt_to_machine() to deal with ioremapped pmd updates. xen/mmu: remove all ad-hoc stats stuff xen: use normal virt_to_machine for ptes xen: make a pile of mmu pvop functions static vmalloc: remove vmalloc_sync_all() from alloc_vm_area() xen: condense everything onto xen_set_pte xen: use mmu_update for xen_set_pte_at() xen: drop all the special iomap pte paths.
2011-05-20xen: fix compile without CONFIG_XEN_DEBUG_FSJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20Use arbitrary_virt_to_machine() to deal with ioremapped pud updates.Jeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20Use arbitrary_virt_to_machine() to deal with ioremapped pmd updates.Jeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20xen/mmu: remove all ad-hoc stats stuffJeremy Fitzhardinge
To make way for tracing. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20xen: use normal virt_to_machine for ptesJeremy Fitzhardinge
We no longer support HIGHPTE allocations, so ptes should always be within the kernel's direct map, and don't need pagetable walks to convert to machine addresses. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20xen: make a pile of mmu pvop functions staticJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20xen: condense everything onto xen_set_pteJeremy Fitzhardinge
xen_set_pte_at and xen_clear_pte are essentially identical to xen_set_pte, so just make them all common. When batched set_pte and pte_clear are the same, but the unbatch operation must be different: they need to update the two halves of the pte in different order. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20xen: use mmu_update for xen_set_pte_at()Jeremy Fitzhardinge
In principle update_va_mapping is a good match for set_pte_at, since it gets the address being mapped, which allows Xen to use its linear pagetable mapping. However that assumes that the pmd for the address is attached to the current pagetable, which may not be true for a given user address space because the kernel pmd is not shared (at least on 32-bit guests). Normally the kernel will automatically sync a missing part of the pagetable with the init_mm pagetable transparently via faults, but that fails when a missing address is passed to Xen. And while the linear pagetable mapping is very useful for 32-bit Xen (as it avoids an explicit domain mapping), 32-bit Xen is deprecated. 64-bit Xen has all memory mapped all the time, so it makes no real difference. The upshot is that we should use mmu_update, since it can operate on non-current pagetables or detached pagetables. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20xen: drop all the special iomap pte paths.Jeremy Fitzhardinge
Xen can work out when we're doing IO mappings for itself, so we don't need to do anything special, and the extra tests just clog things up. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-19Merge branches 'stable/irq', 'stable/p2m.bugfixes', 'stable/e820.bugfixes' ↵Linus Torvalds
and 'stable/mmu.bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen * 'stable/irq' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: do not clear and mask evtchns in __xen_evtchn_do_upcall * 'stable/p2m.bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/p2m: Create entries in the P2M_MFN trees's to track 1-1 mappings * 'stable/e820.bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/setup: Fix for incorrect xen_extra_mem_start initialization under 32-bit xen/setup: Ignore E820_UNUSABLE when setting 1-1 mappings. * 'stable/mmu.bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen mmu: fix a race window causing leave_mm BUG()
2011-05-19arch/x86/xen/mmu: Cleanup code/data sections definitionsDaniel Kiper
Cleanup code/data sections definitions accordingly to include/linux/init.h. Signed-off-by: Daniel Kiper <dkiper@net-space.pl> [v1: Rebased on top of latest linus's to include fixes in mmu.c] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12xen mmu: fix a race window causing leave_mm BUG()Tian, Kevin
There's a race window in xen_drop_mm_ref, where remote cpu may exit dirty bitmap between the check on this cpu and the point where remote cpu handles drop request. So in drop_other_mm_ref we need check whether TLB state is still lazy before calling into leave_mm. This bug is rarely observed in earlier kernel, but exaggerated by the commit 831d52bc153971b70e64eccfbed2b232394f22f8 ("x86, mm: avoid possible bogus tlb entries by clearing prev mm_cpumask after switching mm") which clears bitmap after changing the TLB state. the call trace is as below: --------------------------------- kernel BUG at arch/x86/mm/tlb.c:61! invalid opcode: 0000 [#1] SMP last sysfs file: /sys/devices/system/xen_memory/xen_memory0/info/current_kb CPU 1 Modules linked in: 8021q garp xen_netback xen_blkback blktap blkback_pagemap nbd bridge stp llc autofs4 ipmi_devintf ipmi_si ipmi_msghandler lockd sunrpc bonding ipv6 xenfs dm_multipath video output sbs sbshc parport_pc lp parport ses enclosure snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device serio_raw bnx2 snd_pcm_oss snd_mixer_oss snd_pcm snd_timer iTCO_wdt snd soundcore snd_page_alloc i2c_i801 iTCO_vendor_support i2c_core pcs pkr pata_acpi ata_generic ata_piix shpchp mptsas mptscsih mptbase [last unloaded: freq_table] Pid: 25581, comm: khelper Not tainted 2.6.32.36fixxen #1 Tecal RH2285 RIP: e030:[<ffffffff8103a3cb>] [<ffffffff8103a3cb>] leave_mm+0x15/0x46 RSP: e02b:ffff88002805be48 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88015f8e2da0 RDX: ffff88002805be78 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff88002805be48 R08: ffff88009d662000 R09: dead000000200200 R10: dead000000100100 R11: ffffffff814472b2 R12: ffff88009bfc1880 R13: ffff880028063020 R14: 00000000000004f6 R15: 0000000000000000 FS: 00007f62362d66e0(0000) GS:ffff880028058000(0000) knlGS:0000000000000000 CS: e033 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000003aabc11909 CR3: 000000009b8ca000 CR4: 0000000000002660 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 00000000000000 00 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process khelper (pid: 25581, threadinfo ffff88007691e000, task ffff88009b92db40) Stack: ffff88002805be68 ffffffff8100e4ae 0000000000000001 ffff88009d733b88 <0> ffff88002805be98 ffffffff81087224 ffff88002805be78 ffff88002805be78 <0> ffff88015f808360 00000000000004f6 ffff88002805bea8 ffffffff81010108 Call Trace: <IRQ> [<ffffffff8100e4ae>] drop_other_mm_ref+0x2a/0x53 [<ffffffff81087224>] generic_smp_call_function_single_interrupt+0xd8/0xfc [<ffffffff81010108>] xen_call_function_single_interrupt+0x13/0x28 [<ffffffff810a936a>] handle_IRQ_event+0x66/0x120 [<ffffffff810aac5b>] handle_percpu_irq+0x41/0x6e [<ffffffff8128c1c0>] __xen_evtchn_do_upcall+0x1ab/0x27d [<ffffffff8128dd11>] xen_evtchn_do_upcall+0x33/0x46 [<ffffffff81013efe>] xen_do_hyper visor_callback+0x1e/0x30 <EOI> [<ffffffff814472b2>] ? _spin_unlock_irqrestore+0x15/0x17 [<ffffffff8100f8cf>] ? xen_restore_fl_direct_end+0x0/0x1 [<ffffffff81113f71>] ? flush_old_exec+0x3ac/0x500 [<ffffffff81150dc5>] ? load_elf_binary+0x0/0x17ef [<ffffffff81150dc5>] ? load_elf_binary+0x0/0x17ef [<ffffffff8115115d>] ? load_elf_binary+0x398/0x17ef [<ffffffff81042fcf>] ? need_resched+0x23/0x2d [<ffffffff811f4648>] ? process_measurement+0xc0/0xd7 [<ffffffff81150dc5>] ? load_elf_binary+0x0/0x17ef [<ffffffff81113094>] ? search_binary_handler+0xc8/0x255 [<ffffffff81114362>] ? do_execve+0x1c3/0x29e [<ffffffff8101155d>] ? sys_execve+0x43/0x5d [<ffffffff8106fc45>] ? __call_usermodehelper+0x0/0x6f [<ffffffff81013e28>] ? kernel_execve+0x68/0xd0 [<ffffffff 8106fc45>] ? __call_usermodehelper+0x0/0x6f [<ffffffff8100f8cf>] ? xen_restore_fl_direct_end+0x0/0x1 [<ffffffff8106fb64>] ? ____call_usermodehelper+0x113/0x11e [<ffffffff81013daa>] ? child_rip+0xa/0x20 [<ffffffff8106fc45>] ? __call_usermodehelper+0x0/0x6f [<ffffffff81012f91>] ? int_ret_from_sys_call+0x7/0x1b [<ffffffff8101371d>] ? retint_restore_args+0x5/0x6 [<ffffffff81013da0>] ? child_rip+0x0/0x20 Code: 41 5e 41 5f c9 c3 55 48 89 e5 0f 1f 44 00 00 e8 17 ff ff ff c9 c3 55 48 89 e5 0f 1f 44 00 00 65 8b 04 25 c8 55 01 00 ff c8 75 04 <0f> 0b eb fe 65 48 8b 34 25 c0 55 01 00 48 81 c6 b8 02 00 00 e8 RIP [<ffffffff8103a3cb>] leave_mm+0x15/0x46 RSP <ffff88002805be48> ---[ end trace ce9cee6832a9c503 ]--- Tested-by: Maoxiaoyun<tinnycloud@hotmail.com> Signed-off-by: Kevin Tian <kevin.tian@intel.com> [v1: Fleshed out the git description a bit] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12x86,xen: introduce x86_init.mapping.pagetable_reserveStefano Stabellini
Introduce a new x86_init hook called pagetable_reserve that at the end of init_memory_mapping is used to reserve a range of memory addresses for the kernel pagetable pages we used and free the other ones. On native it just calls memblock_x86_reserve_range while on xen it also takes care of setting the spare memory previously allocated for kernel pagetable pages from RO to RW, so that it can be used for other purposes. A detailed explanation of the reason why this hook is needed follows. As a consequence of the commit: commit 4b239f458c229de044d6905c2b0f9fe16ed9e01e Author: Yinghai Lu <yinghai@kernel.org> Date: Fri Dec 17 16:58:28 2010 -0800 x86-64, mm: Put early page table high at some point init_memory_mapping is going to reach the pagetable pages area and map those pages too (mapping them as normal memory that falls in the range of addresses passed to init_memory_mapping as argument). Some of those pages are already pagetable pages (they are in the range pgt_buf_start-pgt_buf_end) therefore they are going to be mapped RO and everything is fine. Some of these pages are not pagetable pages yet (they fall in the range pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they are going to be mapped RW. When these pages become pagetable pages and are hooked into the pagetable, xen will find that the guest has already a RW mapping of them somewhere and fail the operation. The reason Xen requires pagetables to be RO is that the hypervisor needs to verify that the pagetables are valid before using them. The validation operations are called "pinning" (more details in arch/x86/xen/mmu.c). In order to fix the issue we mark all the pages in the entire range pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation is completed only the range pgt_buf_start-pgt_buf_end is reserved by init_memory_mapping. Hence the kernel is going to crash as soon as one of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those ranges are RO). For this reason we need a hook to reserve the kernel pagetable pages we used and free the other ones so that they can be reused for other purposes. On native it just means calling memblock_x86_reserve_range, on Xen it also means marking RW the pagetable pages that we allocated before but that haven't been used before. Another way to fix this is without using the hook is by adding a 'if (xen_pv_domain)' in the 'init_memory_mapping' code and calling the Xen counterpart, but that is just nasty. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12Revert "xen/mmu: Add workaround "x86-64, mm: Put early page table high""Konrad Rzeszutek Wilk
This reverts commit a38647837a411f7df79623128421eef2118b5884. It does not work with certain AMD machines. last_pfn = 0x100000 max_arch_pfn = 0x400000000 initial memory mapped : 0 - 02c3a000 Base memory trampoline at [ffff88000009b000] 9b000 size 20480 init_memory_mapping: 0000000000000000-0000000100000000 0000000000 - 0100000000 page 4k kernel direct mapping tables up to 100000000 @ ff7fb000-100000000 init_memory_mapping: 0000000100000000-00000001e0800000 0100000000 - 01e0800000 page 4k kernel direct mapping tables up to 1e0800000 @ 1df0f3000-1e0000000 xen: setting RW the range fffdc000 - 100000000 RAMDISK: 0203b000 - 02c3a000 No NUMA configuration found Faking a node at 0000000000000000-00000001e0800000 NUMA: Using 63 for the hash shift. Initmem setup node 0 0000000000000000-00000001e0800000 NODE_DATA [00000001dfffb000 - 00000001dfffffff] BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81cf6a75>] setup_node_bootmem+0x18a/0x1ea PGD 0 Oops: 0003 [#1] SMP last sysfs file: CPU 0 Modules linked in: Pid: 0, comm: swapper Not tainted 2.6.39-0-virtual #6~smb1 RIP: e030:[<ffffffff81cf6a75>] [<ffffffff81cf6a75>] setup_node_bootmem+0x18a/0x1ea RSP: e02b:ffffffff81c01e38 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 00000001e0800000 RCX: 0000000000001040 RDX: 0000000000004100 RSI: 0000000000000000 RDI: ffff8801dfffb000 RBP: ffffffff81c01e58 R08: 0000000000000020 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000bfe400 FS: 0000000000000000(0000) GS:ffffffff81cca000(0000) knlGS:0000000000000000 CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000001c03000 CR4: 0000000000000660 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process swapper (pid: 0, threadinfo ffffffff81c00000, task ffffffff81c0b020) Stack: 0000000000000040 0000000000000001 0000000000000000 ffffffffffffffff ffffffff81c01e88 ffffffff81cf6c25 0000000000000000 0000000000000000 ffffffff81cf687f 0000000000000000 ffffffff81c01ea8 ffffffff81cf6e45 Call Trace: [<ffffffff81cf6c25>] numa_register_memblks.constprop.3+0x150/0x181 [<ffffffff81cf687f>] ? numa_add_memblk+0x7c/0x7c [<ffffffff81cf6e45>] numa_init.part.2+0x1c/0x7c [<ffffffff81cf687f>] ? numa_add_memblk+0x7c/0x7c [<ffffffff81cf6f67>] numa_init+0x6c/0x70 [<ffffffff81cf7057>] initmem_init+0x39/0x3b [<ffffffff81ce5865>] setup_arch+0x64e/0x769 [<ffffffff815e43c1>] ? printk+0x51/0x53 [<ffffffff81cdf92b>] start_kernel+0xd4/0x3f3 [<ffffffff81cdf388>] x86_64_start_reservations+0x132/0x136 [<ffffffff81ce2ed4>] xen_start_kernel+0x588/0x58f Code: 41 00 00 48 8b 3c c5 a0 24 cc 81 31 c0 40 f6 c7 01 74 05 aa 66 ba ff 40 40 f6 c7 02 74 05 66 ab 83 ea 02 89 d1 c1 e9 02 f6 c2 02 <f3> ab 74 02 66 ab 80 e2 01 74 01 aa 49 63 c4 48 c1 eb 0c 44 89 RIP [<ffffffff81cf6a75>] setup_node_bootmem+0x18a/0x1ea RSP <ffffffff81c01e38> CR2: 0000000000000000 ---[ end trace a7919e7f17c0a725 ]--- Kernel panic - not syncing: Attempted to kill the idle task! Pid: 0, comm: swapper Tainted: G D 2.6.39-0-virtual #6~smb1 Reported-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-02xen: mask_rw_pte mark RO all pagetable pages up to pgt_buf_topStefano Stabellini
mask_rw_pte is currently checking if a pfn is a pagetable page if it falls in the range pgt_buf_start - pgt_buf_end but that is incorrect because pgt_buf_end is a moving target: pgt_buf_top is the real boundary. Acked-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-02xen/mmu: Add workaround "x86-64, mm: Put early page table high"Konrad Rzeszutek Wilk
As a consequence of the commit: commit 4b239f458c229de044d6905c2b0f9fe16ed9e01e Author: Yinghai Lu <yinghai@kernel.org> Date: Fri Dec 17 16:58:28 2010 -0800 x86-64, mm: Put early page table high it causes the Linux kernel to crash under Xen: mapping kernel into physical memory Xen: setup ISA identity maps about to get started... (XEN) mm.c:2466:d0 Bad type (saw 7400000000000001 != exp 1000000000000000) for mfn b1d89 (pfn bacf7) (XEN) mm.c:3027:d0 Error while pinning mfn b1d89 (XEN) traps.c:481:d0 Unhandled invalid opcode fault/trap [#6] on VCPU 0 [ec=0000] (XEN) domain_crash_sync called from entry.S (XEN) Domain 0 (vcpu#0) crashed on cpu#0: ... The reason is that at some point init_memory_mapping is going to reach the pagetable pages area and map those pages too (mapping them as normal memory that falls in the range of addresses passed to init_memory_mapping as argument). Some of those pages are already pagetable pages (they are in the range pgt_buf_start-pgt_buf_end) therefore they are going to be mapped RO and everything is fine. Some of these pages are not pagetable pages yet (they fall in the range pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they are going to be mapped RW. When these pages become pagetable pages and are hooked into the pagetable, xen will find that the guest has already a RW mapping of them somewhere and fail the operation. The reason Xen requires pagetables to be RO is that the hypervisor needs to verify that the pagetables are valid before using them. The validation operations are called "pinning" (more details in arch/x86/xen/mmu.c). In order to fix the issue we mark all the pages in the entire range pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation is completed only the range pgt_buf_start-pgt_buf_end is reserved by init_memory_mapping. Hence the kernel is going to crash as soon as one of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those ranges are RO). For this reason, this function is introduced which is called _after_ the init_memory_mapping has completed (in a perfect world we would call this function from init_memory_mapping, but lets ignore that). Because we are called _after_ init_memory_mapping the pgt_buf_[start, end,top] have all changed to new values (b/c another init_memory_mapping is called). Hence, the first time we enter this function, we save away the pgt_buf_start value and update the pgt_buf_[end,top]. When we detect that the "old" pgt_buf_start through pgt_buf_end PFNs have been reserved (so memblock_x86_reserve_range has been called), we immediately set out to RW the "old" pgt_buf_end through pgt_buf_top. And then we update those "old" pgt_buf_[end|top] with the new ones so that we can redo this on the next pagetable. Acked-by: "H. Peter Anvin" <hpa@zytor.com> Reviewed-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> [v1: Updated with Jeremy's comments] [v2: Added the crash output] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-04-20xen: mask_rw_pte: do not apply the early_ioremap checks on x86_32Stefano Stabellini
The two "is_early_ioremap_ptep" checks in mask_rw_pte are only used on x86_64, in fact early_ioremap is not used at all to setup the initial pagetable on x86_32. Moreover on x86_32 the two checks are wrong because the range pgt_buf_start..pgt_buf_end initially should be mapped RW because the pages in the range are not pagetable pages yet and haven't been cleared yet. Afterwards considering the pgt_buf_start..pgt_buf_end is part of the initial mapping, xen_alloc_pte is capable of turning the ptes RO when they become pagetable pages. Fix the issue and improve the readability of the code providing two different implementation of mask_rw_pte for x86_32 and x86_64. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-04-04xen/debug: Don't be so verbose with WARN on 1-1 mapping errors.Konrad Rzeszutek Wilk
There are valid situations in which this error is not a warning. Mainly when QEMU maps a guest memory and uses the VM_IO flag to set the MFNs. For right now make the WARN be WARN_ONCE. In the future we will: 1). Remove the VM_IO code handling.. 2). .. which will also remove this debug facility. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-22Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: xen: update mask_rw_pte after kernel page tables init changes xen: set max_pfn_mapped to the last pfn mapped x86: Cleanup highmap after brk is concluded Fix up trivial onflict (added header file includes) in arch/x86/mm/init_64.c
2011-03-19xen: update mask_rw_pte after kernel page tables init changesStefano Stabellini
After "x86-64, mm: Put early page table high" already existing kernel page table pages can be mapped using early_ioremap too so we need to update mask_rw_pte to make sure these pages are still mapped RO. The reason why we have to do that is explain by the commit message of fef5ba797991f9335bcfc295942b684f9bf613a1: "Xen requires that all pages containing pagetable entries to be mapped read-only. If pages used for the initial pagetable are already mapped then we can change the mapping to RO. However, if they are initially unmapped, we need to make sure that when they are later mapped, they are also mapped RO. ..SNIP.. the pagetable setup code early_ioremaps the pages to write their entries, so we must make sure that mappings created in the early_ioremap fixmap area are mapped RW. (Those mappings are removed before the pages are presented to Xen as pagetable pages.)" We accomplish all this in mask_rw_pte by mapping RO all the pages mapped using early_ioremap apart from the last one that has been allocated because it is not a page table page yet (it has not been hooked into the page tables yet). Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> LKML-Reference: <alpine.DEB.2.00.1103171739050.3382@kaball-desktop> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-03-19xen: set max_pfn_mapped to the last pfn mappedStefano Stabellini
Do not set max_pfn_mapped to the end of the initial memory mappings, that also contain pages that don't belong in pfn space (like the mfn list). Set max_pfn_mapped to the last real pfn mapped in the initial memory mappings that is the pfn backing _end. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> LKML-Reference: <alpine.DEB.2.00.1103171739050.3382@kaball-desktop> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-26 08:28:29 +0000