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2008-10-10x86, cpa: no need to check alias for __set_pages_p/__set_pages_npSuresh Siddha
No alias checking needed for setting present/not-present mapping. Otherwise, we may need to break large pages for 64-bit kernel text mappings (this adds to complexity if we want to do this from atomic context especially, for ex: with CONFIG_DEBUG_PAGEALLOC). Let's keep it simple! Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: arjan@linux.intel.com Cc: venkatesh.pallipadi@intel.com Cc: jeremy@goop.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-10x86, cpa: dont use large pages for kernel identity mapping with DEBUG_PAGEALLOCSuresh Siddha
Don't use large pages for kernel identity mapping with DEBUG_PAGEALLOC. This will remove the need to split the large page for the allocated kernel page in the interrupt context. This will simplify cpa code(as we don't do the split any more from the interrupt context). cpa code simplication in the subsequent patches. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: arjan@linux.intel.com Cc: venkatesh.pallipadi@intel.com Cc: jeremy@goop.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-10x86, cpa: make the kernel physical mapping initialization a two pass sequenceSuresh Siddha
In the first pass, kernel physical mapping will be setup using large or small pages but uses the same PTE attributes as that of the early PTE attributes setup by early boot code in head_[32|64].S After flushing TLB's, we go through the second pass, which setups the direct mapped PTE's with the appropriate attributes (like NX, GLOBAL etc) which are runtime detectable. This two pass mechanism conforms to the TLB app note which says: "Software should not write to a paging-structure entry in a way that would change, for any linear address, both the page size and either the page frame or attributes." Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: arjan@linux.intel.com Cc: venkatesh.pallipadi@intel.com Cc: jeremy@goop.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-06Merge branches 'x86/alternatives', 'x86/cleanups', 'x86/commandline', ↵Ingo Molnar
'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/doc', 'x86/exports', 'x86/fpu', 'x86/gart', 'x86/idle', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/oprofile', 'x86/paravirt', 'x86/reboot', 'x86/sparse-fixes', 'x86/tsc', 'x86/urgent' and 'x86/vmalloc' into x86-v28-for-linus-phase1
2008-10-06Merge branch 'x86/prototypes' into x86-v28-for-linus-phase1Ingo Molnar
Conflicts: arch/x86/kernel/process_32.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-30x86: export set_memory_ro and set_memory_rwBruce Allan
Export set_memory_ro() and set_memory_rw() calls for use by drivers that need to have more debug information about who might be writing to memory space. this was initially developed for use while debugging a memory corruption problem with e1000e. Signed-off-by: Bruce Allan <bruce.w.allan@intel.com> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-26IO resources, x86: ioremap sanity check to catch mapping requests exceeding ↵Suresh Siddha
the BAR sizes Go through the iomem resource tree to check if any of the ioremap() requests span more than any slot in the iomem resource tree and do a WARN_ON() if we hit this check. This will raise a red-flag, if some driver is mapping more than what is needed. And hopefully identify possible corruptions much earlier. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-23Merge branch 'timers/urgent' into x86/xenIngo Molnar
Conflicts: arch/x86/kernel/process_32.c arch/x86/kernel/process_64.c Manual merge: arch/x86/kernel/smpboot.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-14x86/paravirt: Remove duplicate paravirt_pagetable_setup_{start, done}()Alex Nixon
They were already called once in arch/x86/kernel/setup.c - we don't need to call them again. fixes: http://bugzilla.kernel.org/show_bug.cgi?id=11485 Signed-off-by: Alex Nixon <alex.nixon@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-14Merge commit 'v2.6.27-rc6' into x86/patIngo Molnar
2008-09-07x86: add periodic corruption checkHugh Dickins
Perodically check for corruption in low phusical memory. Don't bother checking at fault time, since it won't show anything useful. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-07x86: check for and defend against BIOS memory corruptionJeremy Fitzhardinge
Some BIOSes have been observed to corrupt memory in the low 64k. This change: - Reserves all memory which does not have to be in that area, to prevent it from being used as general memory by the kernel. Things like the SMP trampoline are still in the memory, however. - Clears the reserved memory so we can observe changes to it. - Adds a function check_for_bios_corruption() which checks and reports on memory becoming unexpectedly non-zero. Currently it's called in the x86 fault handler, and the powermanagement debug output. Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-06x86: adjust vmalloc_sync_all() for Xen (2nd try)Jan Beulich
Since the fourth PDPT entry cannot be shared under Xen, vmalloc_sync_all() must iterate over pmd-s rather than pgd-s here. Luckily, the code isn't used for native PAE (SHARED_KERNEL_PMD is 1) and the change is benign to non-PAE. Also do a little more cleanup in that function. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2008-09-06x86: pgd_{c,d}tor() cleanupJan Beulich
Giving pgd_ctor() a properly typed parameter allows eliminating a local variable. Adjust pgd_dtor() to match. Signed-off-by: Jan Beulich <jbeulich@novell.com> Acked-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: "Jeremy Fitzhardinge" <jeremy@goop.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-05x86/paravirt: Remove duplicate paravirt_pagetable_setup_{start, done}()Alex Nixon
They were already called once in arch/x86/kernel/setup.c - we don't need to call them again. Signed-off-by: Alex Nixon <alex.nixon@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-05x86: make sure the CPA test code's use of _PAGE_UNUSED1 is obviousJeremy Fitzhardinge
The CPA test code uses _PAGE_UNUSED1, so make sure its obvious. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-05x86, init_64.c: cleanupIngo Molnar
Clean up comments. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-05x86: move nonx_setup etc from common.c to init_64.cYinghai Lu
like 32 bit put it in init_32.c Signed-off-by: Yinghai <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-04Merge branch 'x86/cpu' into x86/coreH. Peter Anvin
Conflicts: arch/x86/kernel/cpu/feature_names.c include/asm-x86/cpufeature.h
2008-08-25Merge branch 'x86/urgent' into x86/cleanupsIngo Molnar
2008-08-23x86: have set_memory_array_{uc,wb} coalesce memtypes, fixVenki Pallipadi
Fix the start addr for free_memtype calls in the error path. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Acked-by: Rene Herman <rene.herman@keyaccess.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22x86: fix two modpost warnings in mm/init_64.cJan Beulich
early_io{re,un}map() are __init and hence can't be called from __meminit functions. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22x86: fix 1:1 mapping init on 64-bit (memory hotplug case)Jan Beulich
While I don't have a hotplug capable system at hand, I think two issues need fixing: - pud_phys (in kernel_physical_ampping_init()) would remain uninitialized in the after_bootmem case - the locking done just around phys_pmd_{init,update}() would leave out pgd updates, and it was needlessly covering code portions that do allocations (perhaps using a more friendly gfp value in alloc_low_page() would then be possible) Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22x86: have set_memory_array_{uc,wb} coalesce memtypes.Rene Herman
Actually, might as well simply reconstruct the memtype list at free time I guess. How is this for a coalescing version of the array functions? Compiles, boots and provides me with: root@7ixe4:~# wc -l /debug/x86/pat_memtype_list 53 /debug/x86/pat_memtype_list otherwise (down from 16384+). Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22x86: {reverve,free}_memtype() take a physical addressRene Herman
The new set_memory_array_{uc,wb}() pass virtual addresses to {reserve,free}_memtype() it seems. Signed-off-by: Rene Herman <rene.herman@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22Merge branch 'x86/urgent' into x86/patIngo Molnar
Conflicts: arch/x86/mm/pageattr.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-21x86: fix pageattr-testShaohua Li
We changed the interface of some pageattr, this patch makes pageattr-test compile. Signed-off-by: Dave Airlie <airlied@gmail.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-21x86, pageattr: introduce APIs to change pageattr of a page arrayShaohua Li
Add array interface APIs of pageattr. page based cache flush is quite slow for a lot of pages. If pages are more than 1024 (4M), the patch will use a wbinvd(). We have a simple test here (run a 3d game - open arena), nearly all agp memory allocation are small (< 1M), so suppose this will not impact runtime performance. Signed-off-by: Dave Airlie <airlied@gmail.com> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-21Revert "introduce two APIs for page attribute"Ingo Molnar
This reverts commit 1ac2f7d55b7ee1613c90631e87fea22ec06781e5.
2008-08-21devmem, x86: PAT Change /dev/mem mmap with O_SYNC to use UC_MINUSvenkatesh.pallipadi@intel.com
All kernel mappings like ioremap(), etc uses UC_MINUS as the type. /dev/mem mappings with /dev/mem being opened with O_SYNC however was using UC, resulting in a conflict with /dev/mem mmap failing. This seems to be affecting some apps (one being flashrom) which are using O_SYNC and which were working before. Switch /dev/mem with O_SYNC also to UC_MINUS. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-21x86: PAT proper tracking of set_memory_uc and friendsvenkatesh.pallipadi@intel.com
Big thinko in pat memtype tracking code. reserve_memtype should be called with physical address and not virtual address. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-21x86, mmiotrace: silence section mismatch warning - leave_uniprocessorMarcin Slusarz
WARNING: vmlinux.o(.text+0x180af): Section mismatch in reference from the function leave_uniprocessor() to the function .cpuinit.text:cpu_up() The function leave_uniprocessor() references the function __cpuinit cpu_up(). This is often because leave_uniprocessor lacks a __cpuinit annotation or the annotation of cpu_up is wrong. leave_uniprocessor calls cpu_up only when CONFIG_HOTPLUG_CPU is set, so it can be safely annotated as __ref Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com> Cc: Pekka Paalanen <pq@iki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Ingo Molnar <mingo@elte.hu> Cc: Pekka Paalanen <pq@iki.fi>
2008-08-21i386: vmalloc size fixDave Young
Booting kernel with vmalloc=[any size<=16m] will oops on my pc (i386/1G memory). BUG_ON in arch/x86/mm/init_32.c triggered: BUG_ON((unsigned long)high_memory > VMALLOC_START); It's due to the vm area hole. In include/asm-x86/pgtable_32.h: #define VMALLOC_OFFSET (8 * 1024 * 1024) #define VMALLOC_START (((unsigned long)high_memory + 2 * VMALLOC_OFFSET - 1) \ & ~(VMALLOC_OFFSET - 1)) There's several related point: 1. MAXMEM : (-__PAGE_OFFSET - __VMALLOC_RESERVE). The space after VMALLOC_END is included as well, I set it to (VMALLOC_END - PAGE_OFFSET - __VMALLOC_RESERVE) 2. VMALLOC_OFFSET is not considered in __VMALLOC_RESERVE fixed by adding VMALLOC_OFFSET to it. 3. VMALLOC_START : (((unsigned long)high_memory + 2 * VMALLOC_OFFSET - 1) & ~(VMALLOC_OFFSET - 1)) So it's not always 8M, bigger than 8M possible. I set it to ((unsigned long)high_memory + VMALLOC_OFFSET) 4. the VMALLOC_RESERVE is an unused macro, so remove it here. Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Cc: akpm@linux-foundation.org Cc: hidave.darkstar@gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-08-21x86: use WARN() in arch/x86/mm/ioremap.cArjan van de Ven
Use WARN() instead of a printk+WARN_ON() pair; this way the message becomes part of the warning section for better reporting/collection. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: akpm@linux-foundation.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-20x86: another user of PTE_FLAGS_MASKJeremy Fitzhardinge
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-20x86: fix Xorg startup/shutdown slowdown with PATVenki Pallipadi
Rene Herman reported significant Xorg startup/shutdown slowdown due to PAT. It turns out that the memtype list has thousands of entries. Add cached_entry to list add routine, in order to speed up the lookup for sequential reserve_memtype calls. Reported-by: Rene Herman <rene.herman@keyaccess.nl> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-20Merge branch 'linus' into x86/cleanupsIngo Molnar
2008-08-16Merge 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: (32 commits) x86: add MAP_STACK mmap flag x86: fix section mismatch warning - spp_getpage() x86: change init_gdt to update the gdt via write_gdt, rather than a direct write. x86-64: fix overlap of modules and fixmap areas x86, geode-mfgpt: check IRQ before using MFGPT as clocksource x86, acpi: cleanup, temp_stack is used only when CONFIG_SMP is set x86: fix spin_is_contended() x86, nmi: clean UP NMI watchdog failure message x86, NMI: fix watchdog failure message x86: fix /proc/meminfo DirectMap x86: fix readb() et al compile error with gcc-3.2.3 arch/x86/Kconfig: clean up, experimental adjustement x86: invalidate caches before going into suspend x86, perfctr: don't use CCCR_OVF_PMI1 on Pentium 4Ds x86, AMD IOMMU: initialize dma_ops after sysfs registration x86m AMD IOMMU: cleanup: replace LOW_U32 macro with generic lower_32_bits x86, AMD IOMMU: initialize device table properly x86, AMD IOMMU: use status bit instead of memory write-back for completion wait x86: silence mmconfig printk x86, msr: fix NULL pointer deref due to msr_open on nonexistent CPUs ...
2008-08-15x86: fix section mismatch warning - spp_getpage()Marcin Slusarz
WARNING: vmlinux.o(.text+0x17a3e): Section mismatch in reference from the function set_pte_vaddr_pud() to the function .init.text:spp_getpage() The function set_pte_vaddr_pud() references the function __init spp_getpage(). This is often because set_pte_vaddr_pud lacks a __init annotation or the annotation of spp_getpage is wrong. spp_getpage is called from __init (__init_extra_mapping) and non __init (set_pte_vaddr_pud) functions, so it can't be __init. Unfortunately it calls alloc_bootmem_pages which is __init, but does it only when bootmem allocator is available (after_bootmem == 0). So annotate it accordingly. Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com>
2008-08-15x86: Fix ioremap off by one BUGAndi Kleen
Jean Delvare's machine triggered this BUG acpi_os_map_memory phys ffff0000 size 65535 ------------[ cut here ]------------ kernel BUG at arch/x86/mm/pat.c:233! with ACPI in the backtrace. Adding some debugging output showed that ACPI calls acpi_os_map_memory phys ffff0000 size 65535 And ioremap/PAT does this check in 32bit, so addr+size wraps and the BUG in reserve_memtype() triggers incorrectly. BUG_ON(start >= end); /* end is exclusive */ But reserve_memtype already uses u64: int reserve_memtype(u64 start, u64 end, so the 32bit truncation must happen in the caller. Presumably in ioremap when it passes this information to reserve_memtype(). This patch does this computation in 64bit. http://bugzilla.kernel.org/show_bug.cgi?id=11346 Signed-off-by: Andi Kleen <ak@linux.intel.com>
2008-08-15x86, pat: avoid highmem cache attribute aliasingNick Piggin
Highmem code can leave ptes and tlb entries around for a given page even after kunmap, and after it has been freed. >From what I can gather, the PAT code may change the cache attributes of arbitrary physical addresses (ie. including highmem pages), which would result in aliases in the case that it operates on one of these lazy tlb highmem pages. Flushing kmaps should solve the problem. I've also just added code for conditional flushing if we haven't got any dangling highmem aliases -- this should help performance if we change page attributes frequently or systems that aren't using much highmem pages (eg. if < 4G RAM). Should be turned into 2 patches, but just for RFC... Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15introduce two APIs for page attributeShaohua Li
Introduce two APIs for page attribute. flushing tlb/cache in every page attribute is expensive. AGP gart usually will do a lot of operations to change a page to uc, new APIs can reduce flush. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Cc: airlied@linux.ie Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-15x86: fix /proc/meminfo DirectMapHugh Dickins
Do we actually want these DirectMap lines in the x86 /proc/meminfo? I can see they're interesting to CPA developers and TLB optimizers, but they don't fit its usual "where has all my memory gone?" usage. If they are to stay, here are some fixes. 1. On x86_32 without PAE, they're not 2M but 4M pages: no need to mess with the internal enum, but show the right name to users. 2. Many machines can never show anything but 0 for DirectMap1G, so suppress that line unless direct_gbpages are really enabled. 3. The unit in /proc/meminfo is kB not number of pages: HugePages messed that up, but they're an example to regret not to follow. 4. Once we use kB, it's easy to see that 1GB has gone missing (which explains why CONFIG_CPA_DEBUG=y soon wraps DirectMap2M negative): because head_64.S's level2_ident_pgt entries were not counted. My fix is not ideal, but works for more and for less than 1G, and avoids interfering with early bootup pagetable contortions. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-14Merge commit 'v2.6.27-rc3' into x86/prototypesIngo Molnar
Conflicts: include/asm-x86/dma-mapping.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-14x86: don't call e820_regiter_active_regions if out of range on nodeYinghai Lu
so we don't get warning on 32bit system with 64g RAM or more Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-13x86: use WARN() in arch/x86/mm/pageattr.cArjan van de Ven
Use WARN() instead of a printk+WARN_ON() pair; this way the message becomes part of the warning section for better reporting/collection. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: akpm@linux-foundation.org Cc: arjan@linux.intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linusLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: fix spinlock recursion in hvc_console stop_machine: remove unused variable modules: extend initcall_debug functionality to the module loader export virtio_rng.h lguest: use get_user_pages_fast() instead of get_user_pages() mm: Make generic weak get_user_pages_fast and EXPORT_GPL it lguest: don't set MAC address for guest unless specified
2008-08-12mm: Make generic weak get_user_pages_fast and EXPORT_GPL itRusty Russell
Out of line get_user_pages_fast fallback implementation, make it a weak symbol, get rid of CONFIG_HAVE_GET_USER_PAGES_FAST. Export the symbol to modules so lguest can use it. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-08-11x86: compile pat debugfs interface only if CONFIG_X86_PAT is setAndreas Herrmann
Recently I've run a kernel w/o PAT support and wondered why there was a file "x86/pat_memtype_list" in debugfs. Of course it's empty if PAT is disabled ... so just get rid of this interface if PAT is disabled. Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-11x86: work around gcc 3.4.x bugJeremy Fitzhardinge
Simon Horman reported that gcc-3.4.x crashes when compiling pgd_prepopulate_pmd() when PREALLOCATED_PMDS == 0 and CONFIG_DEBUG_INFO is enabled. Adding an extra check for PREALLOCATED_PMDS == 0 [which is compiled out by gcc] seems to avoid the problem. Reported-by: Simon Horman <horms@verge.net.au> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Simon Horman <horms@verge.net.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>