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Violators will be prosecuted for from ; Wed, 29 Jan 2020 22:20:43 -0000 Date: Wed, 29 Jan 2020 23:20:28 +0100 From: Gerald Schaefer Subject: Re: [PATCH V12] mm/debug: Add tests validating architecture page table helpers In-Reply-To: <1580174873-18117-1-git-send-email-anshuman.khandual@arm.com> References: <1580174873-18117-1-git-send-email-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Message-Id: <20200129232028.5a27e656@thinkpad> Sender: linux-s390-owner@vger.kernel.org List-ID: To: Anshuman Khandual Cc: linux-mm@kvack.org, Andrew Morton , Vlastimil Babka , Greg Kroah-Hartman , Thomas Gleixner , Mike Rapoport , Jason Gunthorpe , Dan Williams , Peter Zijlstra , Michal Hocko , Mark Rutland , Mark Brown , Steven Price , Ard Biesheuvel , Masahiro Yamada , Kees Cook , Tetsuo Handa , Matthew Wilcox , Sri Krishna chowdary , Dave Hansen , Russell King - ARM Linux , Michael Ellerman , Paul Mackerras , Martin Schwidefsky , Heiko Carstens , "David S. Miller" , Vineet Gupta , James Hogan , Paul Burton , Ralf Baechle , "Kirill A . Shutemov" , Christophe Leroy , Ingo Molnar , linux-snps-arc@lists.infradead.org, linux-mips@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org On Tue, 28 Jan 2020 06:57:53 +0530 Anshuman Khandual wrote: > This adds tests which will validate architecture page table helpers and > other accessors in their compliance with expected generic MM semantics. > This will help various architectures in validating changes to existing > page table helpers or addition of new ones. > > This test covers basic page table entry transformations including but not > limited to old, young, dirty, clean, write, write protect etc at various > level along with populating intermediate entries with next page table page > and validating them. > > Test page table pages are allocated from system memory with required size > and alignments. The mapped pfns at page table levels are derived from a > real pfn representing a valid kernel text symbol. This test gets called > right after page_alloc_init_late(). > > This gets build and run when CONFIG_DEBUG_VM_PGTABLE is selected along with > CONFIG_VM_DEBUG. Architectures willing to subscribe this test also need to > select CONFIG_ARCH_HAS_DEBUG_VM_PGTABLE which for now is limited to x86 and > arm64. Going forward, other architectures too can enable this after fixing > build or runtime problems (if any) with their page table helpers. > > Folks interested in making sure that a given platform's page table helpers > conform to expected generic MM semantics should enable the above config > which will just trigger this test during boot. Any non conformity here will > be reported as an warning which would need to be fixed. This test will help > catch any changes to the agreed upon semantics expected from generic MM and > enable platforms to accommodate it thereafter. > [...] > > Tested-by: Christophe Leroy #PPC32 Tested-by: Gerald Schaefer # s390 Thanks again for this effort, and for keeping up the spirit against all odds and even after 12 iterations :-) > > diff --git a/Documentation/features/debug/debug-vm-pgtable/arch-support.txt b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt > new file mode 100644 > index 000000000000..f3f8111edbe3 > --- /dev/null > +++ b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt > @@ -0,0 +1,35 @@ > +# > +# Feature name: debug-vm-pgtable > +# Kconfig: ARCH_HAS_DEBUG_VM_PGTABLE > +# description: arch supports pgtable tests for semantics compliance > +# > + ----------------------- > + | arch |status| > + ----------------------- > + | alpha: | TODO | > + | arc: | ok | > + | arm: | TODO | > + | arm64: | ok | > + | c6x: | TODO | > + | csky: | TODO | > + | h8300: | TODO | > + | hexagon: | TODO | > + | ia64: | TODO | > + | m68k: | TODO | > + | microblaze: | TODO | > + | mips: | TODO | > + | nds32: | TODO | > + | nios2: | TODO | > + | openrisc: | TODO | > + | parisc: | TODO | > + | powerpc/32: | ok | > + | powerpc/64: | TODO | > + | riscv: | TODO | > + | s390: | TODO | s390 is ok now, with my patches included in v5.5-rc1. So you can now add --- a/Documentation/features/debug/debug-vm-pgtable/arch-support.txt +++ b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt @@ -25,7 +25,7 @@ | powerpc/32: | ok | | powerpc/64: | TODO | | riscv: | TODO | - | s390: | TODO | + | s390: | ok | | sh: | TODO | | sparc: | TODO | | um: | TODO | --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -59,6 +59,7 @@ config KASAN_SHADOW_OFFSET config S390 def_bool y select ARCH_BINFMT_ELF_STATE + select ARCH_HAS_DEBUG_VM_PGTABLE select ARCH_HAS_DEVMEM_IS_ALLOWED select ARCH_HAS_ELF_RANDOMIZE select ARCH_HAS_FORTIFY_SOURCE