The x86 will crash with linux-next during boot due to this series (v5) with the config below plus CONFIG_DEBUG_VM_PGTABLE=y. I am not sure if v6 would address it. https://raw.githubusercontent.com/cailca/linux-mm/master/x86.config [ 33.862600][ T1] page:ffffea0009000000 is uninitialized and poisoned [ 33.862608][ T1] raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffff871140][ T1] ? _raw_spin_unlock_irq+0x27/0x40 [ 33.871140][ T1] ? rest_init+0x307/0x307 [ 33.871140][ T1] kernel_init+0x11/0x139 [ 33.871140][ T1] ? rest_init+0x307/0x307 [ 33.871140][ T1] ret_from_fork+0x27/0x50 [ 33.871140][ T1] Modules linked in: [ 33.871140][ T1] ---[ end trace e99d392b0f7befbd ]--- [ 33.871140][ T1] RIP: 0010:alloc_gigantic_page_order+0x3fe/0x490 On Tue, 2019-10-15 at 14:51 +0530, Anshuman Khandual wrote: > This series adds a test validation for architecture exported page table > helpers. Patch in the series adds basic transformation tests at various > levels of the page table. Before that it exports gigantic page allocation > function from HugeTLB. > > This test was originally suggested by Catalin during arm64 THP migration > RFC discussion earlier. Going forward it can include more specific tests > with respect to various generic MM functions like THP, HugeTLB etc and > platform specific tests. > > https://lore.kernel.org/linux-mm/20190628102003.GA56463@xxxxxxxxxxxxxxxxxxxx/ > > Changes in V6: > > - Moved alloc_gigantic_page_order() into mm/page_alloc.c per Michal > - Moved alloc_gigantic_page_order() within CONFIG_CONTIG_ALLOC in the test > - Folded Andrew's include/asm-generic/pgtable.h fix into the test patch 2/2 > > Changes in V5: (https://patchwork.kernel.org/project/linux-mm/list/?series=185991) > > - Redefined and moved X86 mm_p4d_folded() into a different header per Kirill/Ingo > - Updated the config option comment per Ingo and dropped 'kernel module' reference > - Updated the commit message and dropped 'kernel module' reference > - Changed DEBUG_ARCH_PGTABLE_TEST into DEBUG_VM_PGTABLE per Ingo > - Moved config option from mm/Kconfig.debug into lib/Kconfig.debug > - Renamed core test function arch_pgtable_tests() as debug_vm_pgtable() > - Renamed mm/arch_pgtable_test.c as mm/debug_vm_pgtable.c > - debug_vm_pgtable() gets called from kernel_init_freeable() after init_mm_internals() > - Added an entry in Documentation/features/debug/ per Ingo > - Enabled the test on arm64 and x86 platforms for now > > Changes in V4: (https://patchwork.kernel.org/project/linux-mm/list/?series=183465) > > - Disable DEBUG_ARCH_PGTABLE_TEST for ARM and IA64 platforms > > Changes in V3: (https://lore.kernel.org/patchwork/project/lkml/list/?series=411216) > > - Changed test trigger from module format into late_initcall() > - Marked all functions with __init to be freed after completion > - Changed all __PGTABLE_PXX_FOLDED checks as mm_pxx_folded() > - Folded in PPC32 fixes from Christophe > > Changes in V2: > > https://lore.kernel.org/linux-mm/1568268173-31302-1-git-send-email-anshuman.khandual@xxxxxxx/T/#t > > - Fixed small typo error in MODULE_DESCRIPTION() > - Fixed m64k build problems for lvalue concerns in pmd_xxx_tests() > - Fixed dynamic page table level folding problems on x86 as per Kirril > - Fixed second pointers during pxx_populate_tests() per Kirill and Gerald > - Allocate and free pte table with pte_alloc_one/pte_free per Kirill > - Modified pxx_clear_tests() to accommodate s390 lower 12 bits situation > - Changed RANDOM_NZVALUE value from 0xbe to 0xff > - Changed allocation, usage, free sequence for saved_ptep > - Renamed VMA_FLAGS as VMFLAGS > - Implemented a new method for random vaddr generation > - Implemented some other cleanups > - Dropped extern reference to mm_alloc() > - Created and exported new alloc_gigantic_page_order() > - Dropped the custom allocator and used new alloc_gigantic_page_order() > > Changes in V1: > > https://lore.kernel.org/linux-mm/1567497706-8649-1-git-send-email-anshuman.khandual@xxxxxxx/ > > - Added fallback mechanism for PMD aligned memory allocation failure > > Changes in RFC V2: > > https://lore.kernel.org/linux-mm/1565335998-22553-1-git-send-email-anshuman.khandual@xxxxxxx/T/#u > > - Moved test module and it's config from lib/ to mm/ > - Renamed config TEST_ARCH_PGTABLE as DEBUG_ARCH_PGTABLE_TEST > - Renamed file from test_arch_pgtable.c to arch_pgtable_test.c > - Added relevant MODULE_DESCRIPTION() and MODULE_AUTHOR() details > - Dropped loadable module config option > - Basic tests now use memory blocks with required size and alignment > - PUD aligned memory block gets allocated with alloc_contig_range() > - If PUD aligned memory could not be allocated it falls back on PMD aligned > memory block from page allocator and pud_* tests are skipped > - Clear and populate tests now operate on real in memory page table entries > - Dummy mm_struct gets allocated with mm_alloc() > - Dummy page table entries get allocated with [pud|pmd|pte]_alloc_[map]() > - Simplified [p4d|pgd]_basic_tests(), now has random values in the entries > > Original RFC V1: > > https://lore.kernel.org/linux-mm/1564037723-26676-1-git-send-email-anshuman.khandual@xxxxxxx/ > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Vlastimil Babka <vbabka@xxxxxxx> > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> > Cc: Jason Gunthorpe <jgg@xxxxxxxx> > Cc: Dan Williams <dan.j.williams@xxxxxxxxx> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxxxx> > Cc: Mark Rutland <mark.rutland@xxxxxxx> > Cc: Mark Brown <broonie@xxxxxxxxxx> > Cc: Steven Price <Steven.Price@xxxxxxx> > Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> > Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > Cc: Kees Cook <keescook@xxxxxxxxxxxx> > Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> > Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> > Cc: Sri Krishna chowdary <schowdary@xxxxxxxxxx> > Cc: Dave Hansen <dave.hansen@xxxxxxxxx> > Cc: Russell King - ARM Linux <linux@xxxxxxxxxxxxxxx> > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > Cc: Paul Mackerras <paulus@xxxxxxxxx> > Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> > Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> > Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx> > Cc: James Hogan <jhogan@xxxxxxxxxx> > Cc: Paul Burton <paul.burton@xxxxxxxx> > Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> > Cc: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> > Cc: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx> > Cc: Christophe Leroy <christophe.leroy@xxxxxx> > Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> > Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx > Cc: linux-mips@xxxxxxxxxxxxxxx > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > Cc: linux-ia64@xxxxxxxxxxxxxxx > Cc: linuxppc-dev@xxxxxxxxxxxxxxxx > Cc: linux-s390@xxxxxxxxxxxxxxx > Cc: linux-sh@xxxxxxxxxxxxxxx > Cc: sparclinux@xxxxxxxxxxxxxxx > Cc: x86@xxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > > > Anshuman Khandual (2): > mm/page_alloc: Make alloc_gigantic_page() available for general use > mm/debug: Add tests validating architecture page table helpers > > .../debug/debug-vm-pgtable/arch-support.txt | 34 ++ > arch/arm64/Kconfig | 1 + > arch/x86/Kconfig | 1 + > arch/x86/include/asm/pgtable_64.h | 6 + > include/asm-generic/pgtable.h | 6 + > include/linux/gfp.h | 3 + > init/main.c | 1 + > lib/Kconfig.debug | 21 + > mm/Makefile | 1 + > mm/debug_vm_pgtable.c | 450 ++++++++++++++++++ > mm/hugetlb.c | 76 +-- > mm/page_alloc.c | 98 ++++ > 12 files changed, 623 insertions(+), 75 deletions(-) > create mode 100644 Documentation/features/debug/debug-vm-pgtable/arch-support.txt > create mode 100644 mm/debug_vm_pgtable.c >
