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* Merge tag 'powerpc-5.19-1' of ↵Linus Torvalds2022-05-287-13/+43
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Convert to the generic mmap support (ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT) - Add support for outline-only KASAN with 64-bit Radix MMU (P9 or later) - Increase SIGSTKSZ and MINSIGSTKSZ and add support for AT_MINSIGSTKSZ - Enable the DAWR (Data Address Watchpoint) on POWER9 DD2.3 or later - Drop support for system call instruction emulation - Many other small features and fixes Thanks to Alexey Kardashevskiy, Alistair Popple, Andy Shevchenko, Bagas Sanjaya, Bjorn Helgaas, Bo Liu, Chen Huang, Christophe Leroy, Colin Ian King, Daniel Axtens, Dwaipayan Ray, Fabiano Rosas, Finn Thain, Frank Rowand, Fuqian Huang, Guilherme G. Piccoli, Hangyu Hua, Haowen Bai, Haren Myneni, Hari Bathini, He Ying, Jason Wang, Jiapeng Chong, Jing Yangyang, Joel Stanley, Julia Lawall, Kajol Jain, Kevin Hao, Krzysztof Kozlowski, Laurent Dufour, Lv Ruyi, Madhavan Srinivasan, Magali Lemes, Miaoqian Lin, Minghao Chi, Nathan Chancellor, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Oscar Salvador, Pali Rohár, Paul Mackerras, Peng Wu, Qing Wang, Randy Dunlap, Reza Arbab, Russell Currey, Sohaib Mohamed, Vaibhav Jain, Vasant Hegde, Wang Qing, Wang Wensheng, Xiang wangx, Xiaomeng Tong, Xu Wang, Yang Guang, Yang Li, Ye Bin, YueHaibing, Yu Kuai, Zheng Bin, Zou Wei, and Zucheng Zheng. * tag 'powerpc-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (200 commits) powerpc/64: Include cache.h directly in paca.h powerpc/64s: Only set HAVE_ARCH_UNMAPPED_AREA when CONFIG_PPC_64S_HASH_MMU is set powerpc/xics: Include missing header powerpc/powernv/pci: Drop VF MPS fixup powerpc/fsl_book3e: Don't set rodata RO too early powerpc/microwatt: Add mmu bits to device tree powerpc/powernv/flash: Check OPAL flash calls exist before using powerpc/powermac: constify device_node in of_irq_parse_oldworld() powerpc/powermac: add missing g5_phy_disable_cpu1() declaration selftests/powerpc/pmu: fix spelling mistake "mis-match" -> "mismatch" powerpc: Enable the DAWR on POWER9 DD2.3 and above powerpc/64s: Add CPU_FTRS_POWER10 to ALWAYS mask powerpc/64s: Add CPU_FTRS_POWER9_DD2_2 to CPU_FTRS_ALWAYS mask powerpc: Fix all occurences of "the the" selftests/powerpc/pmu/ebb: remove fixed_instruction.S powerpc/platforms/83xx: Use of_device_get_match_data() powerpc/eeh: Drop redundant spinlock initialization powerpc/iommu: Add missing of_node_put in iommu_init_early_dart powerpc/pseries/vas: Call misc_deregister if sysfs init fails powerpc/papr_scm: Fix leaking nvdimm_events_map elements ...
| * powerpc/64s: Only set HAVE_ARCH_UNMAPPED_AREA when CONFIG_PPC_64S_HASH_MMU ↵Christophe Leroy2022-05-241-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | is set When CONFIG_PPC_64S_HASH_MMU is not set, slice.c is not built and arch_get_unmapped_area() and arch_get_unmapped_area_topdown() are not provided because RADIX uses the generic ones. Therefore, neither set HAVE_ARCH_UNMAPPED_AREA nor HAVE_ARCH_UNMAPPED_AREA_TOPDOWN. Fixes: ab57bd7570d4 ("powerpc/mm: Move get_unmapped_area functions to slice.c") Reported-by: Laurent Dufour <ldufour@linux.ibm.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Tested-by: Laurent Dufour <ldufour@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/e438c6cc09f94085e56733ed2d6e84333c35292a.1653370913.git.christophe.leroy@csgroup.eu
| * powerpc: Book3S 64-bit outline-only KASAN supportDaniel Axtens2022-05-223-3/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement a limited form of KASAN for Book3S 64-bit machines running under the Radix MMU, supporting only outline mode. - Enable the compiler instrumentation to check addresses and maintain the shadow region. (This is the guts of KASAN which we can easily reuse.) - Require kasan-vmalloc support to handle modules and anything else in vmalloc space. - KASAN needs to be able to validate all pointer accesses, but we can't instrument all kernel addresses - only linear map and vmalloc. On boot, set up a single page of read-only shadow that marks all iomap and vmemmap accesses as valid. - Document KASAN in powerpc docs. Background ---------- KASAN support on Book3S is a bit tricky to get right: - It would be good to support inline instrumentation so as to be able to catch stack issues that cannot be caught with outline mode. - Inline instrumentation requires a fixed offset. - Book3S runs code with translations off ("real mode") during boot, including a lot of generic device-tree parsing code which is used to determine MMU features. [ppc64 mm note: The kernel installs a linear mapping at effective address c000...-c008.... This is a one-to-one mapping with physical memory from 0000... onward. Because of how memory accesses work on powerpc 64-bit Book3S, a kernel pointer in the linear map accesses the same memory both with translations on (accessing as an 'effective address'), and with translations off (accessing as a 'real address'). This works in both guests and the hypervisor. For more details, see s5.7 of Book III of version 3 of the ISA, in particular the Storage Control Overview, s5.7.3, and s5.7.5 - noting that this KASAN implementation currently only supports Radix.] - Some code - most notably a lot of KVM code - also runs with translations off after boot. - Therefore any offset has to point to memory that is valid with translations on or off. One approach is just to give up on inline instrumentation. This way boot-time checks can be delayed until after the MMU is set is up, and we can just not instrument any code that runs with translations off after booting. Take this approach for now and require outline instrumentation. Previous attempts allowed inline instrumentation. However, they came with some unfortunate restrictions: only physically contiguous memory could be used and it had to be specified at compile time. Maybe we can do better in the future. [paulus@ozlabs.org - Rebased onto 5.17. Note that a kernel with CONFIG_KASAN=y will crash during boot on a machine using HPT translation because not all the entry points to the generic KASAN code are protected with a call to kasan_arch_is_ready().] Originally-by: Balbir Singh <bsingharora@gmail.com> # ppc64 out-of-line radix version Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> [mpe: Update copyright year and comment formatting] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/YoTE69OQwiG7z+Gu@cleo
| * powerpc/mm: Move get_unmapped_area functions to slice.cChristophe Leroy2022-05-052-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | hugetlb_get_unmapped_area() is now identical to the generic version if only RADIX is enabled, so move it to slice.c and let it fallback on the generic one when HASH MMU is not compiled in. Do the same with arch_get_unmapped_area() and arch_get_unmapped_area_topdown(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b5d9c124e82889e0cb115c150915a0c0d84eb960.1649523076.git.christophe.leroy@csgroup.eu
| * powerpc/mm: Use generic_hugetlb_get_unmapped_area()Christophe Leroy2022-05-051-4/+0
| | | | | | | | | | | | | | | | | | | | Use the generic version of arch_hugetlb_get_unmapped_area() which is now available at all time. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/05f77014c619061638ecc52a0a4136eb04cc2799.1649523076.git.christophe.leroy@csgroup.eu
| * powerpc/mm: Make slice specific to book3s/64Christophe Leroy2022-05-052-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 555904d07eef ("powerpc/8xx: MM_SLICE is not needed anymore") only book3s/64 selects CONFIG_PPC_MM_SLICES. Move slice.c into mm/book3s64/ Move necessary stuff in asm/book3s/64/slice.h and remove asm/slice.h Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4a0d74ef1966a5902b5fd4ac4b513a760a6d675a.1649523076.git.christophe.leroy@csgroup.eu
* | powerpc/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE for book3sDavid Hildenbrand2022-05-091-1/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Right now, the last 5 bits (0x1f) of the swap entry are used for the type and the bit before that (0x20) is used for _PAGE_SWP_SOFT_DIRTY. We cannot use 0x40, as that collides with _RPAGE_RSV1 -- contained in _PAGE_HPTEFLAGS. The next candidate would be _RPAGE_SW3 (0x200) -- which is used for _PAGE_SOFT_DIRTY for !swp ptes. So let's just use _PAGE_SOFT_DIRTY for _PAGE_SWP_SOFT_DIRTY (to make it easier to grasp) and use 0x20 now for _PAGE_SWP_EXCLUSIVE. Link: https://lkml.kernel.org/r/20220329164329.208407-9-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Don Dutile <ddutile@redhat.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Liang Zhang <zhangliang5@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Nadav Amit <namit@vmware.com> Cc: Oded Gabbay <oded.gabbay@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pedro Demarchi Gomes <pedrodemargomes@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | powerpc/pgtable: remove _PAGE_BIT_SWAP_TYPE for book3sDavid Hildenbrand2022-05-091-7/+5
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The swap type is simply stored in bits 0x1f of the swap pte. Let's simplify by just getting rid of _PAGE_BIT_SWAP_TYPE. It's not like that we can simply change it: _PAGE_SWP_SOFT_DIRTY would suddenly fall into _RPAGE_RSV1, which isn't possible and would make the BUILD_BUG_ON(_PAGE_HPTEFLAGS & _PAGE_SWP_SOFT_DIRTY) angry. While at it, make it clearer which bit we're actually using for _PAGE_SWP_SOFT_DIRTY by just using the proper define and introduce and use SWP_TYPE_MASK. Link: https://lkml.kernel.org/r/20220329164329.208407-8-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Don Dutile <ddutile@redhat.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Liang Zhang <zhangliang5@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Nadav Amit <namit@vmware.com> Cc: Oded Gabbay <oded.gabbay@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pedro Demarchi Gomes <pedrodemargomes@gmail.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'powerpc-5.18-1' of ↵Linus Torvalds2022-03-252-17/+24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Livepatch support for 32-bit is probably the standout new feature, otherwise mostly just lots of bits and pieces all over the board. There's a series of commits cleaning up function descriptor handling, which touches a few other arches as well as LKDTM. It has acks from Arnd, Kees and Helge. Summary: - Enforce kernel RO, and implement STRICT_MODULE_RWX for 603. - Add support for livepatch to 32-bit. - Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS. - Merge vdso64 and vdso32 into a single directory. - Fix build errors with newer binutils. - Add support for UADDR64 relocations, which are emitted by some toolchains. This allows powerpc to build with the latest lld. - Fix (another) potential userspace r13 corruption in transactional memory handling. - Cleanups of function descriptor handling & related fixes to LKDTM. Thanks to Abdul Haleem, Alexey Kardashevskiy, Anders Roxell, Aneesh Kumar K.V, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Bhaskar Chowdhury, Cédric Le Goater, Chen Jingwen, Christophe JAILLET, Christophe Leroy, Corentin Labbe, Daniel Axtens, Daniel Henrique Barboza, David Dai, Fabiano Rosas, Ganesh Goudar, Guo Zhengkui, Hangyu Hua, Haren Myneni, Hari Bathini, Igor Zhbanov, Jakob Koschel, Jason Wang, Jeremy Kerr, Joachim Wiberg, Jordan Niethe, Julia Lawall, Kajol Jain, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mamatha Inamdar, Maxime Bizon, Maxim Kiselev, Maxim Kochetkov, Michal Suchanek, Nageswara R Sastry, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nour-eddine Taleb, Paul Menzel, Ping Fang, Pratik R. Sampat, Randy Dunlap, Ritesh Harjani, Rohan McLure, Russell Currey, Sachin Sant, Segher Boessenkool, Shivaprasad G Bhat, Sourabh Jain, Thierry Reding, Tobias Waldekranz, Tyrel Datwyler, Vaibhav Jain, Vladimir Oltean, Wedson Almeida Filho, and YueHaibing" * tag 'powerpc-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits) powerpc/pseries: Fix use after free in remove_phb_dynamic() powerpc/time: improve decrementer clockevent processing powerpc/time: Fix KVM host re-arming a timer beyond decrementer range powerpc/tm: Fix more userspace r13 corruption powerpc/xive: fix return value of __setup handler powerpc/64: Add UADDR64 relocation support powerpc: 8xx: fix a return value error in mpc8xx_pic_init powerpc/ps3: remove unneeded semicolons powerpc/64: Force inlining of prevent_user_access() and set_kuap() powerpc/bitops: Force inlining of fls() powerpc: declare unmodified attribute_group usages const powerpc/spufs: Fix build warning when CONFIG_PROC_FS=n powerpc/secvar: fix refcount leak in format_show() powerpc/64e: Tie PPC_BOOK3E_64 to PPC_FSL_BOOK3E powerpc: Move C prototypes out of asm-prototypes.h powerpc/kexec: Declare kexec_paca static powerpc/smp: Declare current_set static powerpc: Cleanup asm-prototypes.c powerpc/ftrace: Use STK_GOT in ftrace_mprofile.S powerpc/ftrace: Regroup PPC64 specific operations in ftrace_mprofile.S ...
| * powerpc/64: Force inlining of prevent_user_access() and set_kuap()Christophe Leroy2022-03-081-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A ppc64_defconfig build exhibits about 10 copied of prevent_user_access(). It also have one copy of set_kuap(). c000000000017340 <.prevent_user_access.constprop.0>: c00000000001a038: 4b ff d3 09 bl c000000000017340 <.prevent_user_access.constprop.0> c00000000001aabc: 4b ff c8 85 bl c000000000017340 <.prevent_user_access.constprop.0> c00000000001ab38: 4b ff c8 09 bl c000000000017340 <.prevent_user_access.constprop.0> c00000000001ade0: 4b ff c5 61 bl c000000000017340 <.prevent_user_access.constprop.0> c000000000039b90 <.prevent_user_access.constprop.0>: c00000000003ac08: 4b ff ef 89 bl c000000000039b90 <.prevent_user_access.constprop.0> c00000000003b9d0: 4b ff e1 c1 bl c000000000039b90 <.prevent_user_access.constprop.0> c00000000003ba54: 4b ff e1 3d bl c000000000039b90 <.prevent_user_access.constprop.0> c00000000003bbfc: 4b ff df 95 bl c000000000039b90 <.prevent_user_access.constprop.0> c00000000015dde0 <.prevent_user_access.constprop.0>: c0000000001612c0: 4b ff cb 21 bl c00000000015dde0 <.prevent_user_access.constprop.0> c000000000161b54: 4b ff c2 8d bl c00000000015dde0 <.prevent_user_access.constprop.0> c000000000188cf0 <.prevent_user_access.constprop.0>: c00000000018d658: 4b ff b6 99 bl c000000000188cf0 <.prevent_user_access.constprop.0> c00000000030fe20 <.prevent_user_access.constprop.0>: c0000000003123d4: 4b ff da 4d bl c00000000030fe20 <.prevent_user_access.constprop.0> c000000000313970: 4b ff c4 b1 bl c00000000030fe20 <.prevent_user_access.constprop.0> c0000000005e6bd0 <.prevent_user_access.constprop.0>: c0000000005e7d8c: 4b ff ee 45 bl c0000000005e6bd0 <.prevent_user_access.constprop.0> c0000000007bcae0 <.prevent_user_access.constprop.0>: c0000000007bda10: 4b ff f0 d1 bl c0000000007bcae0 <.prevent_user_access.constprop.0> c0000000007bda54: 4b ff f0 8d bl c0000000007bcae0 <.prevent_user_access.constprop.0> c0000000007bdd28: 4b ff ed b9 bl c0000000007bcae0 <.prevent_user_access.constprop.0> c0000000007c0390: 4b ff c7 51 bl c0000000007bcae0 <.prevent_user_access.constprop.0> c00000000094e4f0 <.prevent_user_access.constprop.0>: c000000000950e40: 4b ff d6 b1 bl c00000000094e4f0 <.prevent_user_access.constprop.0> c00000000097d2d0 <.prevent_user_access.constprop.0>: c0000000009813fc: 4b ff be d5 bl c00000000097d2d0 <.prevent_user_access.constprop.0> c000000000acd540 <.prevent_user_access.constprop.0>: c000000000ad1d60: 4b ff b7 e1 bl c000000000acd540 <.prevent_user_access.constprop.0> c000000000e5d680 <.prevent_user_access.constprop.0>: c000000000e64b60: 4b ff 8b 21 bl c000000000e5d680 <.prevent_user_access.constprop.0> c000000000e64b6c: 4b ff 8b 15 bl c000000000e5d680 <.prevent_user_access.constprop.0> c000000000e64c38: 4b ff 8a 49 bl c000000000e5d680 <.prevent_user_access.constprop.0> When building signal_64.c with -Winline the following messages appear: ./arch/powerpc/include/asm/book3s/64/kup.h:331:20: error: inlining failed in call to 'set_kuap': call is unlikely and code size would grow [-Werror=inline] ./arch/powerpc/include/asm/book3s/64/kup.h:401:20: error: inlining failed in call to 'prevent_user_access.constprop': call is unlikely and code size would grow [-Werror=inline] Those functions are used on hot pathes and have been expected to be inlined at all time. Force them inline. This patch reduces the kernel text size by 700 bytes, confirming that not inlining those functions is not worth it. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/eff9b2b211957fa2e8707e46f31674097fd563a3.1644588972.git.christophe.leroy@csgroup.eu
| * powerpc/32s: Make pte_update() non atomic on 603 coreChristophe Leroy2022-02-031-15/+22
| | | | | | | | | | | | | | | | | | | | On 603 core, TLB miss handler don't do any change to the page tables so pte_update() doesn't need to be atomic. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/cc89d3c11fc9c742d0df3454a657a3a00be24046.1643538554.git.christophe.leroy@csgroup.eu
* | Merge tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds2022-03-221-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull folio updates from Matthew Wilcox: - Rewrite how munlock works to massively reduce the contention on i_mmap_rwsem (Hugh Dickins): https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/ - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph Hellwig): https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/ - Convert GUP to use folios and make pincount available for order-1 pages. (Matthew Wilcox) - Convert a few more truncation functions to use folios (Matthew Wilcox) - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew Wilcox) - Convert rmap_walk to use folios (Matthew Wilcox) - Convert most of shrink_page_list() to use a folio (Matthew Wilcox) - Add support for creating large folios in readahead (Matthew Wilcox) * tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits) mm/damon: minor cleanup for damon_pa_young selftests/vm/transhuge-stress: Support file-backed PMD folios mm/filemap: Support VM_HUGEPAGE for file mappings mm/readahead: Switch to page_cache_ra_order mm/readahead: Align file mappings for non-DAX mm/readahead: Add large folio readahead mm: Support arbitrary THP sizes mm: Make large folios depend on THP mm: Fix READ_ONLY_THP warning mm/filemap: Allow large folios to be added to the page cache mm: Turn can_split_huge_page() into can_split_folio() mm/vmscan: Convert pageout() to take a folio mm/vmscan: Turn page_check_references() into folio_check_references() mm/vmscan: Account large folios correctly mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios mm/vmscan: Free non-shmem folios without splitting them mm/rmap: Constify the rmap_walk_control argument mm/rmap: Convert rmap_walk() to take a folio mm: Turn page_anon_vma() into folio_anon_vma() mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read() ...
| * | powerpc: Add pmd_pfn()Matthew Wilcox (Oracle)2022-03-211-2/+2
| |/ | | | | | | | | | | | | This is straightforward for everything except nohash64 where we indirect through pmd_page(). There must be a better way to do this. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
* / powerpc/64s: Fix build failure when CONFIG_PPC_64S_HASH_MMU is not setMurilo Opsfelder Araujo2022-03-051-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following build failure occurs when CONFIG_PPC_64S_HASH_MMU is not set: arch/powerpc/kernel/setup_64.c: In function ‘setup_per_cpu_areas’: arch/powerpc/kernel/setup_64.c:811:21: error: ‘mmu_linear_psize’ undeclared (first use in this function); did you mean ‘mmu_virtual_psize’? 811 | if (mmu_linear_psize == MMU_PAGE_4K) | ^~~~~~~~~~~~~~~~ | mmu_virtual_psize arch/powerpc/kernel/setup_64.c:811:21: note: each undeclared identifier is reported only once for each function it appears in Move the declaration of mmu_linear_psize outside of CONFIG_PPC_64S_HASH_MMU ifdef. After the above is fixed, it fails later with the following error: ld: arch/powerpc/kexec/file_load_64.o: in function `.arch_kexec_kernel_image_probe': file_load_64.c:(.text+0x1c1c): undefined reference to `.add_htab_mem_range' Fix that, too, by conditioning add_htab_mem_range() symbol to CONFIG_PPC_64S_HASH_MMU. Fixes: 387e220a2e5e ("powerpc/64s: Move hash MMU support code under CONFIG_PPC_64S_HASH_MMU") Reported-by: Erhard F. <erhard_f@mailbox.org> Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215567 Link: https://lore.kernel.org/r/20220301204743.45133-1-muriloo@linux.ibm.com
* powerpc/fixmap: Fix VM debug warning on unmapChristophe Leroy2022-01-242-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unmapping a fixmap entry is done by calling __set_fixmap() with FIXMAP_PAGE_CLEAR as flags. Today, powerpc __set_fixmap() calls map_kernel_page(). map_kernel_page() is not happy when called a second time for the same page. WARNING: CPU: 0 PID: 1 at arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8 CPU: 0 PID: 1 Comm: swapper Not tainted 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty #682 NIP: c0017cd4 LR: c00187f0 CTR: 00000010 REGS: e1011d50 TRAP: 0700 Not tainted (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty) MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42000208 XER: 00000000 GPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c GPR08: 00001000 b00045a9 00000001 c0f58460 c0f50000 00000000 c0007e10 00000000 GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 GPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000 NIP [c0017cd4] set_pte_at+0xc/0x1e8 LR [c00187f0] map_kernel_page+0x9c/0x100 Call Trace: [e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (unreliable) [e1011e30] [c0165fec] __set_fixmap+0x30/0x44 [e1011e40] [c0c13bdc] early_iounmap+0x11c/0x170 [e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0 [e1011e90] [c0c03634] do_one_initcall+0x80/0x178 [e1011ef0] [c0c0385c] kernel_init_freeable+0xb4/0x250 [e1011f20] [c0007e34] kernel_init+0x24/0x140 [e1011f30] [c0016268] ret_from_kernel_thread+0x5c/0x64 Instruction dump: 7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010 4e800020 81250000 712a0001 41820008 <0fe00000> 9421ffe0 93e1001c 48000030 Implement unmap_kernel_page() which clears an existing pte. Reported-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Tested-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b0b752f6f6ecc60653e873f385c6f0dce4e9ab6a.1638789098.git.christophe.leroy@csgroup.eu
* powerpc/32s: Fix kasan_init_region() for KASANChristophe Leroy2022-01-161-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It has been reported some configuration where the kernel doesn't boot with KASAN enabled. This is due to wrong BAT allocation for the KASAN area: ---[ Data Block Address Translation ]--- 0: 0xc0000000-0xcfffffff 0x00000000 256M Kernel rw m 1: 0xd0000000-0xdfffffff 0x10000000 256M Kernel rw m 2: 0xe0000000-0xefffffff 0x20000000 256M Kernel rw m 3: 0xf8000000-0xf9ffffff 0x2a000000 32M Kernel rw m 4: 0xfa000000-0xfdffffff 0x2c000000 64M Kernel rw m A BAT must have both virtual and physical addresses alignment matching the size of the BAT. This is not the case for BAT 4 above. Fix kasan_init_region() by using block_size() function that is in book3s32/mmu.c. To be able to reuse it here, make it non static and change its name to bat_block_size() in order to avoid name conflict with block_size() defined in <linux/blkdev.h> Also reuse find_free_bat() to avoid an error message from setbat() when no BAT is available. And allocate memory outside of linear memory mapping to avoid wasting that precious space. With this change we get correct alignment for BATs and KASAN shadow memory is allocated outside the linear memory space. ---[ Data Block Address Translation ]--- 0: 0xc0000000-0xcfffffff 0x00000000 256M Kernel rw 1: 0xd0000000-0xdfffffff 0x10000000 256M Kernel rw 2: 0xe0000000-0xefffffff 0x20000000 256M Kernel rw 3: 0xf8000000-0xfbffffff 0x7c000000 64M Kernel rw 4: 0xfc000000-0xfdffffff 0x7a000000 32M Kernel rw Fixes: 7974c4732642 ("powerpc/32s: Implement dedicated kasan_init_region()") Cc: stable@vger.kernel.org Reported-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Tested-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7a50ef902494d1325227d47d33dada01e52e5518.1641818726.git.christophe.leroy@csgroup.eu
* powerpc/pseries: Add __init attribute to eligible functionsNick Child2021-12-231-1/+1
| | | | | | | | | | | | Some functions defined in 'arch/powerpc/platforms/pseries' are deserving of an `__init` macro attribute. These functions are only called by other initialization functions and therefore should inherit the attribute. Also, change function declarations in header files to include `__init`. Signed-off-by: Nick Child <nick.child@ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211216220035.605465-13-nick.child@ibm.com
* powerpc/kuap: Prepare for supporting KUAP on BOOK3E/64Christophe Leroy2021-12-091-0/+9
| | | | | | | | | | | | | | | Also call kuap_lock() and kuap_save_and_lock() from interrupt functions with CONFIG_PPC64. For book3s/64 we keep them empty as it is done in assembly. Also do the locked assert when switching task unless it is book3s/64. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1cbf94e26e6d6e2e028fd687588a7e6622d454a6.1634627931.git.christophe.leroy@csgroup.eu
* powerpc/kuap: Add kuap_lock()Christophe Leroy2021-12-091-5/+9
| | | | | | | | | | | | | | | Add kuap_lock() and call it when entering interrupts from user. It is called kuap_lock() as it is similar to kuap_save_and_lock() without the save. However book3s/32 already have a kuap_lock(). Rename it kuap_lock_addr(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4437e2deb9f6f549f7089d45e9c6f96a7e77905a.1634627931.git.christophe.leroy@csgroup.eu
* powerpc/kuap: Remove __kuap_assert_locked()Christophe Leroy2021-12-092-11/+0
| | | | | | | | | | | | | __kuap_assert_locked() is redundant with __kuap_get_and_assert_locked(). Move the verification of CONFIG_PPC_KUAP_DEBUG in kuap_assert_locked() and make it call __kuap_get_and_assert_locked() directly. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1a60198a25d2ba38a37f1b92bc7d096435df4224.1634627931.git.christophe.leroy@csgroup.eu
* powerpc/kuap: Check KUAP activation in generic functionsChristophe Leroy2021-12-092-50/+25
| | | | | | | | | | | | Today, every platform checks that KUAP is not de-activated before doing the real job. Move the verification out of platform specific functions. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/894f110397fcd248e125fb855d1e863e4e633a0d.1634627931.git.christophe.leroy@csgroup.eu
* powerpc/kuap: Add a generic intermediate layerChristophe Leroy2021-12-092-17/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | Make the following functions generic to all platforms. - bad_kuap_fault() - kuap_assert_locked() - kuap_save_and_lock() (PPC32 only) - kuap_kernel_restore() - kuap_get_and_assert_locked() And for all platforms except book3s/64 - allow_user_access() - prevent_user_access() - prevent_user_access_return() - restore_user_access() Prepend __ in front of the name of platform specific ones. For now the generic just calls the platform specific, but next patch will move redundant parts of specific functions into the generic one. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/eaef143a8dae7288cd34565ffa7b49c16aee1ec3.1634627931.git.christophe.leroy@csgroup.eu
* powerpc/32s: Save content of sr0 to avoid 'mfsr'Christophe Leroy2021-12-091-0/+5
| | | | | | | | | | | | | | | | | | | | Calling 'mfsr' to get the content of segment registers is heavy, in addition it requires clearing of the 'reserved' bits. In order to avoid this operation, save it in mm context and in thread struct. The saved sr0 is the one used by kernel, this means that on locking entry it can be used as is. For unlocking, the only thing to do is to clear SR_NX. This improves null_syscall selftest by 12 cycles, ie 4%. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b02baf2ed8f09bad910dfaeeb7353b2ae6830525.1634627931.git.christophe.leroy@csgroup.eu
* powerpc/32s: Do kuep_lock() and kuep_unlock() in assemblyChristophe Leroy2021-12-092-35/+76
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When interrupt and syscall entries where converted to C, KUEP locking and unlocking was also converted. It improved performance by unrolling the loop, and allowed easily implementing boot time deactivation of KUEP. However, null_syscall selftest shows that KUEP is still heavy (361 cycles with KUEP, 212 cycles without). A way to improve more is to group 'mtsr's together, instead of repeating 'addi' + 'mtsr' several times. In order to do that, more registers need to be available. In C, GCC will always be able to provide the requested number of registers, but at the cost of saving some data on the stack, which is counter performant here. So let's do it in assembly, when we have full control of which register can be used. It also has the advantage of locking earlier and unlocking later and it helps GCC generating less tricky code. The only drawback is to make boot time deactivation less straight forward and require 'hand' instruction patching. Group 'mtsr's by 4. With this change, null_syscall selftest reports 336 cycles. Without the change it was 361 cycles, that's a 7% reduction. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/115cb279e9b9948dfd93a065e047081c59e3a2a6.1634627931.git.christophe.leroy@csgroup.eu
* powerpc/32s: Remove capability to disable KUEP at boottimeChristophe Leroy2021-12-091-2/+1
| | | | | | | | | | | | Disabling KUEP at boottime makes things unnecessarily complex. Still allow disabling KUEP at build time, but when it's built-in it is always there. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/96f583f82423a29a4205c60b9721079111b35567.1634627931.git.christophe.leroy@csgroup.eu
* powerpc/64s: Move hash MMU support code under CONFIG_PPC_64S_HASH_MMUNicholas Piggin2021-12-094-4/+35
| | | | | | | | | | | | | Compiling out hash support code when CONFIG_PPC_64S_HASH_MMU=n saves 128kB kernel image size (90kB text) on powernv_defconfig minus KVM, 350kB on pseries_defconfig minus KVM, 40kB on a tiny config. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Fixup defined(ARCH_HAS_MEMREMAP_COMPAT_ALIGN), which needs CONFIG. Fix radix_enabled() use in setup_initial_memory_limit(). Add some stubs to reduce number of ifdefs.] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211201144153.2456614-18-npiggin@gmail.com
* powerpc/64s: Always define arch unmapped area callsNicholas Piggin2021-12-092-4/+6
| | | | | | | | | | | To avoid any functional changes to radix paths when building with hash MMU support disabled (and CONFIG_PPC_MM_SLICES=n), always define the arch get_unmapped_area calls on 64s platforms. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211201144153.2456614-16-npiggin@gmail.com
* powerpc/pseries: Stop selecting PPC_HASH_MMU_NATIVENicholas Piggin2021-12-021-4/+0
| | | | | | | | | | | | The pseries platform does not use the native hash code but the PAPR virtualised hash interfaces, so remove PPC_HASH_MMU_NATIVE. This requires moving tlbiel code from hash_native.c to hash_utils.c. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211201144153.2456614-4-npiggin@gmail.com
* powerpc/64s: Get LPID bit width from device treeNicholas Piggin2021-11-301-4/+5
| | | | | | | | | | | | | | | | | | | | | Allow the LPID bit width and partition table size to be set at runtime from the device tree. Move the PID bit width detection into the same place. KVM does not support using the extra bits yet, this is mainly required to get the PTCR register values correct (so KVM will run but it will not allocate > 4096 LPIDs). OPAL firmware provides this property for POWER10 CPUs since skiboot commit 9b85f7d961f2 ("hdata: add mmu-pid-bits and mmu-lpid-bits for POWER10 CPUs"). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211129030915.1888332-1-npiggin@gmail.com
* Merge tag 'powerpc-5.16-1' of ↵Linus Torvalds2021-11-053-0/+15
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Enable STRICT_KERNEL_RWX for Freescale 85xx platforms. - Activate CONFIG_STRICT_KERNEL_RWX by default, while still allowing it to be disabled. - Add support for out-of-line static calls on 32-bit. - Fix oopses doing bpf-to-bpf calls when STRICT_KERNEL_RWX is enabled. - Fix boot hangs on e5500 due to stale value in ESR passed to do_page_fault(). - Fix several bugs on pseries in handling of device tree cache information for hotplugged CPUs, and/or during partition migration. - Various other small features and fixes. Thanks to Alexey Kardashevskiy, Alistair Popple, Anatolij Gustschin, Andrew Donnellan, Athira Rajeev, Bixuan Cui, Bjorn Helgaas, Cédric Le Goater, Christophe Leroy, Daniel Axtens, Daniel Henrique Barboza, Denis Kirjanov, Fabiano Rosas, Frederic Barrat, Gustavo A. R. Silva, Hari Bathini, Jacques de Laval, Joel Stanley, Kai Song, Kajol Jain, Laurent Vivier, Leonardo Bras, Madhavan Srinivasan, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Niklas Schnelle, Oliver O'Halloran, Rob Herring, Russell Currey, Srikar Dronamraju, Stan Johnson, Tyrel Datwyler, Uwe Kleine-König, Vasant Hegde, Wan Jiabing, and Xiaoming Ni, * tag 'powerpc-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (73 commits) powerpc/8xx: Fix Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST powerpc/32e: Ignore ESR in instruction storage interrupt handler powerpc/powernv/prd: Unregister OPAL_MSG_PRD2 notifier during module unload powerpc: Don't provide __kernel_map_pages() without ARCH_SUPPORTS_DEBUG_PAGEALLOC MAINTAINERS: Update powerpc KVM entry powerpc/xmon: fix task state output powerpc/44x/fsp2: add missing of_node_put powerpc/dcr: Use cmplwi instead of 3-argument cmpli KVM: PPC: Tick accounting should defer vtime accounting 'til after IRQ handling powerpc/security: Use a mutex for interrupt exit code patching powerpc/83xx/mpc8349emitx: Make mcu_gpiochip_remove() return void powerpc/fsl_booke: Fix setting of exec flag when setting TLBCAMs powerpc/book3e: Fix set_memory_x() and set_memory_nx() powerpc/nohash: Fix __ptep_set_access_flags() and ptep_set_wrprotect() powerpc/bpf: Fix write protecting JIT code selftests/powerpc: Use date instead of EPOCHSECONDS in mitigation-patching.sh powerpc/64s/interrupt: Fix check_return_regs_valid() false positive powerpc/boot: Set LC_ALL=C in wrapper script powerpc/64s: Default to 64K pages for 64 bit book3s Revert "powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC" ...
| * powerpc/s64: Clarify that radix lacks DEBUG_PAGEALLOCJoel Stanley2021-10-223-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The page_alloc.c code will call into __kernel_map_pages() when DEBUG_PAGEALLOC is configured and enabled. As the implementation assumes hash, this should crash spectacularly if not for a bit of luck in __kernel_map_pages(). In this function linear_map_hash_count is always zero, the for loop exits without doing any damage. There are no other platforms that determine if they support debug_pagealloc at runtime. Instead of adding code to mm/page_alloc.c to do that, this change turns the map/unmap into a noop when in radix mode and prints a warning once. Signed-off-by: Joel Stanley <joel@jms.id.au> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Reformat if per Christophe's suggestion] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211013213438.675095-1-joel@jms.id.au
* | powerpc/32s: Fix kuap_kernel_restore()Christophe Leroy2021-10-071-0/+8
|/ | | | | | | | | | | | | | | | | | | | | At interrupt exit, kuap_kernel_restore() calls kuap_unlock() with the value contained in regs->kuap. However, when regs->kuap contains 0xffffffff it means that KUAP was not unlocked so calling kuap_unlock() is unrelevant and results in jeopardising the contents of kernel space segment registers. So check that regs->kuap doesn't contain KUAP_NONE before calling kuap_unlock(). In the meantime it also means that if KUAP has not been correcly locked back at interrupt exit, it must be locked before continuing. This is done by checking the content of current->thread.kuap which was returned by kuap_get_and_assert_locked() Fixes: 16132529cee5 ("powerpc/32s: Rework Kernel Userspace Access Protection") Reported-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/0d0c4d0f050a637052287c09ba521bad960a2790.1631715131.git.christophe.leroy@csgroup.eu
* Merge branch 'fixes' into nextMichael Ellerman2021-09-031-0/+20
|\ | | | | | | | | | | | | | | | | | | | | Merge our fixes branch into next. That lets us resolve a conflict in arch/powerpc/sysdev/xive/common.c. Between cbc06f051c52 ("powerpc/xive: Do not skip CPU-less nodes when creating the IPIs"), which moved request_irq() out of xive_init_ipis(), and 17df41fec5b8 ("powerpc: use IRQF_NO_DEBUG for IPIs") which added IRQF_NO_DEBUG to that request_irq() call, which has now moved.
| * powerpc/32s: Fix random crashes by adding isync() after locking/unlocking KUEPChristophe Leroy2021-08-191-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit b5efec00b671 ("powerpc/32s: Move KUEP locking/unlocking in C") removed the 'isync' instruction after adding/removing NX bit in user segments. The reasoning behind this change was that when setting the NX bit we don't mind it taking effect with delay as the kernel never executes text from userspace, and when clearing the NX bit this is to return to userspace and then the 'rfi' should synchronise the context. However, it looks like on book3s/32 having a hash page table, at least on the G3 processor, we get an unexpected fault from userspace, then this is followed by something wrong in the verification of MSR_PR at end of another interrupt. This is fixed by adding back the removed isync() following update of NX bit in user segment registers. Only do it for cores with an hash table, as 603 cores don't exhibit that problem and the two isync increase ./null_syscall selftest by 6 cycles on an MPC 832x. First problem: unexpected WARN_ON() for mysterious PROTFAULT WARNING: CPU: 0 PID: 1660 at arch/powerpc/mm/fault.c:354 do_page_fault+0x6c/0x5b0 Modules linked in: CPU: 0 PID: 1660 Comm: Xorg Not tainted 5.13.0-pmac-00028-gb3c15b60339a #40 NIP: c001b5c8 LR: c001b6f8 CTR: 00000000 REGS: e2d09e40 TRAP: 0700 Not tainted (5.13.0-pmac-00028-gb3c15b60339a) MSR: 00021032 <ME,IR,DR,RI> CR: 42d04f30 XER: 20000000 GPR00: c000424c e2d09f00 c301b680 e2d09f40 0000001e 42000000 00cba028 00000000 GPR08: 08000000 48000010 c301b680 e2d09f30 22d09f30 00c1fff0 00cba000 a7b7ba4c GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010 GPR24: a7b7b64c a7b7d2f0 00000004 00000000 c1efa6c0 00cba02c 00000300 e2d09f40 NIP [c001b5c8] do_page_fault+0x6c/0x5b0 LR [c001b6f8] do_page_fault+0x19c/0x5b0 Call Trace: [e2d09f00] [e2d09f04] 0xe2d09f04 (unreliable) [e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4 --- interrupt: 300 at 0xa7a261dc NIP: a7a261dc LR: a7a253bc CTR: 00000000 REGS: e2d09f40 TRAP: 0300 Not tainted (5.13.0-pmac-00028-gb3c15b60339a) MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 228428e2 XER: 20000000 DAR: 00cba02c DSISR: 42000000 GPR00: a7a27448 afa6b0e0 a74c35c0 a7b7b614 0000001e a7b7b614 00cba028 00000000 GPR08: 00020fd9 00000031 00cb9ff8 a7a273b0 220028e2 00c1fff0 00cba000 a7b7ba4c GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010 GPR24: a7b7b64c a7b7d2f0 00000004 00000002 0000001e a7b7b614 a7b7aff4 00000030 NIP [a7a261dc] 0xa7a261dc LR [a7a253bc] 0xa7a253bc --- interrupt: 300 Instruction dump: 7c4a1378 810300a0 75278410 83820298 83a300a4 553b018c 551e0036 4082038c 2e1b0000 40920228 75280800 41820220 <0fe00000> 3b600000 41920214 81420594 Second problem: MSR PR is seen unset allthough the interrupt frame shows it set kernel BUG at arch/powerpc/kernel/interrupt.c:458! Oops: Exception in kernel mode, sig: 5 [#1] BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac Modules linked in: CPU: 0 PID: 1660 Comm: Xorg Tainted: G W 5.13.0-pmac-00028-gb3c15b60339a #40 NIP: c0011434 LR: c001629c CTR: 00000000 REGS: e2d09e70 TRAP: 0700 Tainted: G W (5.13.0-pmac-00028-gb3c15b60339a) MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42d09f30 XER: 00000000 GPR00: 00000000 e2d09f30 c301b680 e2d09f40 83440000 c44d0e68 e2d09e8c 00000000 GPR08: 00000002 00dc228a 00004000 e2d09f30 22d09f30 00c1fff0 afa6ceb4 00c26144 GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000 GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089 NIP [c0011434] interrupt_exit_kernel_prepare+0x10/0x70 LR [c001629c] interrupt_return+0x9c/0x144 Call Trace: [e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4 (unreliable) --- interrupt: 300 at 0xa09be008 NIP: a09be008 LR: a09bdfe8 CTR: a09bdfc0 REGS: e2d09f40 TRAP: 0300 Tainted: G W (5.13.0-pmac-00028-gb3c15b60339a) MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 420028e2 XER: 20000000 DAR: a539a308 DSISR: 0a000000 GPR00: a7b90d50 afa6b2d0 a74c35c0 a0a8b690 a0a8b698 a5365d70 a4fa82a8 00000004 GPR08: 00000000 a09bdfc0 00000000 a5360000 a09bde7c 00c1fff0 afa6ceb4 00c26144 GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000 GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089 NIP [a09be008] 0xa09be008 LR [a09bdfe8] 0xa09bdfe8 --- interrupt: 300 Instruction dump: 80010024 83e1001c 7c0803a6 4bffff80 3bc00800 4bffffd0 486b42fd 4bffffcc 81430084 71480002 41820038 554a0462 <0f0a0000> 80620060 74630001 40820034 Fixes: b5efec00b671 ("powerpc/32s: Move KUEP locking/unlocking in C") Cc: stable@vger.kernel.org # v5.13+ Reported-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4856f5574906e2aec0522be17bf3848a22b2cd0b.1629269345.git.christophe.leroy@csgroup.eu
* | powerpc/bug: Provide better flexibility to WARN_ON/__WARN_FLAGS() with asm gotoChristophe Leroy2021-08-151-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using asm goto in __WARN_FLAGS() and WARN_ON() allows more flexibility to GCC. For that add an entry to the exception table so that program_check_exception() knowns where to resume execution after a WARNING. Here are two exemples. The first one is done on PPC32 (which benefits from the previous patch), the second is on PPC64. unsigned long test(struct pt_regs *regs) { int ret; WARN_ON(regs->msr & MSR_PR); return regs->gpr[3]; } unsigned long test9w(unsigned long a, unsigned long b) { if (WARN_ON(!b)) return 0; return a / b; } Before the patch: 000003a8 <test>: 3a8: 81 23 00 84 lwz r9,132(r3) 3ac: 71 29 40 00 andi. r9,r9,16384 3b0: 40 82 00 0c bne 3bc <test+0x14> 3b4: 80 63 00 0c lwz r3,12(r3) 3b8: 4e 80 00 20 blr 3bc: 0f e0 00 00 twui r0,0 3c0: 80 63 00 0c lwz r3,12(r3) 3c4: 4e 80 00 20 blr 0000000000000bf0 <.test9w>: bf0: 7c 89 00 74 cntlzd r9,r4 bf4: 79 29 d1 82 rldicl r9,r9,58,6 bf8: 0b 09 00 00 tdnei r9,0 bfc: 2c 24 00 00 cmpdi r4,0 c00: 41 82 00 0c beq c0c <.test9w+0x1c> c04: 7c 63 23 92 divdu r3,r3,r4 c08: 4e 80 00 20 blr c0c: 38 60 00 00 li r3,0 c10: 4e 80 00 20 blr After the patch: 000003a8 <test>: 3a8: 81 23 00 84 lwz r9,132(r3) 3ac: 71 29 40 00 andi. r9,r9,16384 3b0: 40 82 00 0c bne 3bc <test+0x14> 3b4: 80 63 00 0c lwz r3,12(r3) 3b8: 4e 80 00 20 blr 3bc: 0f e0 00 00 twui r0,0 0000000000000c50 <.test9w>: c50: 7c 89 00 74 cntlzd r9,r4 c54: 79 29 d1 82 rldicl r9,r9,58,6 c58: 0b 09 00 00 tdnei r9,0 c5c: 7c 63 23 92 divdu r3,r3,r4 c60: 4e 80 00 20 blr c70: 38 60 00 00 li r3,0 c74: 4e 80 00 20 blr In the first exemple, we see GCC doesn't need to duplicate what happens after the trap. In the second exemple, we see that GCC doesn't need to emit a test and a branch in the likely path in addition to the trap. We've got some WARN_ON() in .softirqentry.text section so it needs to be added in the OTHER_TEXT_SECTIONS in modpost.c Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/389962b1b702e3c78d169e59bcfac56282889173.1618331882.git.christophe.leroy@csgroup.eu
* powerpc/book3s64/mm: update flush_tlb_range to flush page walk cacheAneesh Kumar K.V2021-07-081-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | flush_tlb_range is special in that we don't specify the page size used for the translation. Hence when flushing TLB we flush the translation cache for all possible page sizes. The kernel also uses the same interface when moving page tables around. Such a move requires us to flush the page walk cache. Instead of adding another interface to force page walk cache flush, update flush_tlb_range to flush page walk cache if the range flushed is more than the PMD range. A page table move will always involve an invalidate range more than PMD_SIZE. Running microbenchmark with mprotect and parallel memory access didn't show any observable performance impact. Link: https://lkml.kernel.org/r/20210616045735.374532-3-aneesh.kumar@linux.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Hugh Dickins <hughd@google.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Kalesh Singh <kaleshsingh@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: rename p4d_page_vaddr to p4d_pgtable and make it return pud_t *Aneesh Kumar K.V2021-07-081-1/+4
| | | | | | | | | | | | | | | | | | | | | No functional change in this patch. [aneesh.kumar@linux.ibm.com: m68k build error reported by kernel robot] Link: https://lkml.kernel.org/r/87tulxnb2v.fsf@linux.ibm.com Link: https://lkml.kernel.org/r/20210615110859.320299-2-aneesh.kumar@linux.ibm.com Link: https://lore.kernel.org/linuxppc-dev/CAHk-=wi+J+iodze9FtjM3Zi4j4OeS+qqbKxME9QN4roxPEXH9Q@mail.gmail.com/ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Hugh Dickins <hughd@google.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Kalesh Singh <kaleshsingh@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: rename pud_page_vaddr to pud_pgtable and make it return pmd_t *Aneesh Kumar K.V2021-07-081-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | No functional change in this patch. [aneesh.kumar@linux.ibm.com: fix] Link: https://lkml.kernel.org/r/87wnqtnb60.fsf@linux.ibm.com [sfr@canb.auug.org.au: another fix] Link: https://lkml.kernel.org/r/20210619134410.89559-1-aneesh.kumar@linux.ibm.com Link: https://lkml.kernel.org/r/20210615110859.320299-1-aneesh.kumar@linux.ibm.com Link: https://lore.kernel.org/linuxppc-dev/CAHk-=wi+J+iodze9FtjM3Zi4j4OeS+qqbKxME9QN4roxPEXH9Q@mail.gmail.com/ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Hugh Dickins <hughd@google.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Kalesh Singh <kaleshsingh@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'powerpc-5.14-1' of ↵Linus Torvalds2021-07-026-114/+211
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - A big series refactoring parts of our KVM code, and converting some to C. - Support for ARCH_HAS_SET_MEMORY, and ARCH_HAS_STRICT_MODULE_RWX on some CPUs. - Support for the Microwatt soft-core. - Optimisations to our interrupt return path on 64-bit. - Support for userspace access to the NX GZIP accelerator on PowerVM on Power10. - Enable KUAP and KUEP by default on 32-bit Book3S CPUs. - Other smaller features, fixes & cleanups. Thanks to: Andy Shevchenko, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev, Baokun Li, Benjamin Herrenschmidt, Bharata B Rao, Christophe Leroy, Daniel Axtens, Daniel Henrique Barboza, Finn Thain, Geoff Levand, Haren Myneni, Jason Wang, Jiapeng Chong, Joel Stanley, Jordan Niethe, Kajol Jain, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Paul Mackerras, Russell Currey, Sathvika Vasireddy, Shaokun Zhang, Stephen Rothwell, Sudeep Holla, Suraj Jitindar Singh, Tom Rix, Vaibhav Jain, YueHaibing, Zhang Jianhua, and Zhen Lei. * tag 'powerpc-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (218 commits) powerpc: Only build restart_table.c for 64s powerpc/64s: move ret_from_fork etc above __end_soft_masked powerpc/64s/interrupt: clean up interrupt return labels powerpc/64/interrupt: add missing kprobe annotations on interrupt exit symbols powerpc/64: enable MSR[EE] in irq replay pt_regs powerpc/64s/interrupt: preserve regs->softe for NMI interrupts powerpc/64s: add a table of implicit soft-masked addresses powerpc/64e: remove implicit soft-masking and interrupt exit restart logic powerpc/64e: fix CONFIG_RELOCATABLE build warnings powerpc/64s: fix hash page fault interrupt handler powerpc/4xx: Fix setup_kuep() on SMP powerpc/32s: Fix setup_{kuap/kuep}() on SMP powerpc/interrupt: Use names in check_return_regs_valid() powerpc/interrupt: Also use exit_must_hard_disable() on PPC32 powerpc/sysfs: Replace sizeof(arr)/sizeof(arr[0]) with ARRAY_SIZE powerpc/ptrace: Refactor regs_set_return_{msr/ip} powerpc/ptrace: Move set_return_regs_changed() before regs_set_return_{msr/ip} powerpc/stacktrace: Fix spurious "stale" traces in raise_backtrace_ipi() powerpc/pseries/vas: Include irqdomain.h powerpc: mark local variables around longjmp as volatile ...
| * Merge branch 'topic/ppc-kvm' into nextMichael Ellerman2021-06-232-0/+5
| |\ | | | | | | | | | | | | | | | Pull in some more ppc KVM patches we are keeping in our topic branch. In particular this brings in the series to add H_RPT_INVALIDATE.
| * | powerpc: Define swapper_pg_dir[] in CChristophe Leroy2021-06-171-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't duplicate swapper_pg_dir[] in each platform's head.S Define it in mm/pgtable.c Define MAX_PTRS_PER_PGD because on book3s/64 PTRS_PER_PGD is not a constant. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/5e3f1b8a4695c33ccc80aa3870e016bef32b85e1.1623063174.git.christophe.leroy@csgroup.eu
| * | powerpc/kuap: Remove to/from/size parameters of prevent_user_access()Christophe Leroy2021-06-172-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | prevent_user_access() doesn't use anymore to/from/size parameters. Remove them. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b7113662fd2c26e4c33e9d705de324bd3860822e.1622708530.git.christophe.leroy@csgroup.eu
| * | powerpc/kuap: Remove KUAP_CURRENT_XXXChristophe Leroy2021-06-171-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | book3s/32 was the only user of KUAP_CURRENT_XXX. After rework of book3s/32 KUAP, it is not used anymore. Remove them. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/549214ecf6887d965645e664520d4886663c5ffb.1622708530.git.christophe.leroy@csgroup.eu
| * | powerpc/32s: Rework Kernel Userspace Access ProtectionChristophe Leroy2021-06-171-71/+79
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On book3s/32, KUAP is provided by toggling Ks bit in segment registers. One segment register addresses 256M of virtual memory. At the time being, KUAP implements a complex logic to apply the unlock/lock on the exact number of segments covering the user range to access, with saving the boundaries of the range of segments in a member of thread struct. But most if not all user accesses are within a single segment. Rework KUAP with a different approach: - Open only one segment, the one corresponding to the starting address of the range to be accessed. - If a second segment is involved, it will generate a page fault. The segment will then be open by the page fault handler. The kuap member of thread struct will now contain: - The start address of the current on going user access, that will be used to know which segment to lock at the end of the user access. - ~0 when no user access is open - ~1 when additionnal segments are opened by a page fault. Then, at lock time - When only one segment is open, close it. - When several segments are open, close all user segments. Almost 100% of the time, only one segment will be involved. In interrupts, inline the function that unlock/lock all segments, because not inlining them implies a lot of register save/restore. With the patch, writing value 128 in userspace in perf_copy_attr() is done with 16 instructions: 3890: 93 82 04 dc stw r28,1244(r2) 3894: 7d 20 e5 26 mfsrin r9,r28 3898: 55 29 00 80 rlwinm r9,r9,0,2,0 389c: 7d 20 e1 e4 mtsrin r9,r28 38a0: 4c 00 01 2c isync 38a4: 39 20 00 80 li r9,128 38a8: 91 3c 00 00 stw r9,0(r28) 38ac: 81 42 04 dc lwz r10,1244(r2) 38b0: 39 00 ff ff li r8,-1 38b4: 91 02 04 dc stw r8,1244(r2) 38b8: 2c 0a ff fe cmpwi r10,-2 38bc: 41 82 00 88 beq 3944 <perf_copy_attr+0x36c> 38c0: 7d 20 55 26 mfsrin r9,r10 38c4: 65 29 40 00 oris r9,r9,16384 38c8: 7d 20 51 e4 mtsrin r9,r10 38cc: 4c 00 01 2c isync ... 3944: 48 00 00 01 bl 3944 <perf_copy_attr+0x36c> 3944: R_PPC_REL24 kuap_lock_all_ool Before the patch it was 118 instructions. In reality only 42 are executed in most cases, but GCC is not able to see that a properly aligned user access cannot involve more than one segment. 5060: 39 1d 00 04 addi r8,r29,4 5064: 3d 20 b0 00 lis r9,-20480 5068: 7c 08 48 40 cmplw r8,r9 506c: 40 81 00 08 ble 5074 <perf_copy_attr+0x2cc> 5070: 3d 00 b0 00 lis r8,-20480 5074: 39 28 ff ff addi r9,r8,-1 5078: 57 aa 00 06 rlwinm r10,r29,0,0,3 507c: 55 29 27 3e rlwinm r9,r9,4,28,31 5080: 39 29 00 01 addi r9,r9,1 5084: 7d 29 53 78 or r9,r9,r10 5088: 91 22 04 dc stw r9,1244(r2) 508c: 7d 20 ed 26 mfsrin r9,r29 5090: 55 29 00 80 rlwinm r9,r9,0,2,0 5094: 7c 08 50 40 cmplw r8,r10 5098: 40 81 00 c0 ble 5158 <perf_copy_attr+0x3b0> 509c: 7d 46 50 f8 not r6,r10 50a0: 7c c6 42 14 add r6,r6,r8 50a4: 54 c6 27 be rlwinm r6,r6,4,30,31 50a8: 7d 20 51 e4 mtsrin r9,r10 50ac: 3c ea 10 00 addis r7,r10,4096 50b0: 39 29 01 11 addi r9,r9,273 50b4: 7f 88 38 40 cmplw cr7,r8,r7 50b8: 55 29 02 06 rlwinm r9,r9,0,8,3 50bc: 40 9d 00 9c ble cr7,5158 <perf_copy_attr+0x3b0> 50c0: 2f 86 00 00 cmpwi cr7,r6,0 50c4: 41 9e 00 4c beq cr7,5110 <perf_copy_attr+0x368> 50c8: 2f 86 00 01 cmpwi cr7,r6,1 50cc: 41 9e 00 2c beq cr7,50f8 <perf_copy_attr+0x350> 50d0: 2f 86 00 02 cmpwi cr7,r6,2 50d4: 41 9e 00 14 beq cr7,50e8 <perf_copy_attr+0x340> 50d8: 7d 20 39 e4 mtsrin r9,r7 50dc: 39 29 01 11 addi r9,r9,273 50e0: 3c e7 10 00 addis r7,r7,4096 50e4: 55 29 02 06 rlwinm r9,r9,0,8,3 50e8: 7d 20 39 e4 mtsrin r9,r7 50ec: 39 29 01 11 addi r9,r9,273 50f0: 3c e7 10 00 addis r7,r7,4096 50f4: 55 29 02 06 rlwinm r9,r9,0,8,3 50f8: 7d 20 39 e4 mtsrin r9,r7 50fc: 3c e7 10 00 addis r7,r7,4096 5100: 39 29 01 11 addi r9,r9,273 5104: 7f 88 38 40 cmplw cr7,r8,r7 5108: 55 29 02 06 rlwinm r9,r9,0,8,3 510c: 40 9d 00 4c ble cr7,5158 <perf_copy_attr+0x3b0> 5110: 7d 20 39 e4 mtsrin r9,r7 5114: 39 29 01 11 addi r9,r9,273 5118: 3c c7 10 00 addis r6,r7,4096 511c: 55 29 02 06 rlwinm r9,r9,0,8,3 5120: 7d 20 31 e4 mtsrin r9,r6 5124: 39 29 01 11 addi r9,r9,273 5128: 3c c6 10 00 addis r6,r6,4096 512c: 55 29 02 06 rlwinm r9,r9,0,8,3 5130: 7d 20 31 e4 mtsrin r9,r6 5134: 39 29 01 11 addi r9,r9,273 5138: 3c c7 30 00 addis r6,r7,12288 513c: 55 29 02 06 rlwinm r9,r9,0,8,3 5140: 7d 20 31 e4 mtsrin r9,r6 5144: 3c e7 40 00 addis r7,r7,16384 5148: 39 29 01 11 addi r9,r9,273 514c: 7f 88 38 40 cmplw cr7,r8,r7 5150: 55 29 02 06 rlwinm r9,r9,0,8,3 5154: 41 9d ff bc bgt cr7,5110 <perf_copy_attr+0x368> 5158: 4c 00 01 2c isync 515c: 39 20 00 80 li r9,128 5160: 91 3d 00 00 stw r9,0(r29) 5164: 38 e0 00 00 li r7,0 5168: 90 e2 04 dc stw r7,1244(r2) 516c: 7d 20 ed 26 mfsrin r9,r29 5170: 65 29 40 00 oris r9,r9,16384 5174: 40 81 00 c0 ble 5234 <perf_copy_attr+0x48c> 5178: 7d 47 50 f8 not r7,r10 517c: 7c e7 42 14 add r7,r7,r8 5180: 54 e7 27 be rlwinm r7,r7,4,30,31 5184: 7d 20 51 e4 mtsrin r9,r10 5188: 3d 4a 10 00 addis r10,r10,4096 518c: 39 29 01 11 addi r9,r9,273 5190: 7c 08 50 40 cmplw r8,r10 5194: 55 29 02 06 rlwinm r9,r9,0,8,3 5198: 40 81 00 9c ble 5234 <perf_copy_attr+0x48c> 519c: 2c 07 00 00 cmpwi r7,0 51a0: 41 82 00 4c beq 51ec <perf_copy_attr+0x444> 51a4: 2c 07 00 01 cmpwi r7,1 51a8: 41 82 00 2c beq 51d4 <perf_copy_attr+0x42c> 51ac: 2c 07 00 02 cmpwi r7,2 51b0: 41 82 00 14 beq 51c4 <perf_copy_attr+0x41c> 51b4: 7d 20 51 e4 mtsrin r9,r10 51b8: 39 29 01 11 addi r9,r9,273 51bc: 3d 4a 10 00 addis r10,r10,4096 51c0: 55 29 02 06 rlwinm r9,r9,0,8,3 51c4: 7d 20 51 e4 mtsrin r9,r10 51c8: 39 29 01 11 addi r9,r9,273 51cc: 3d 4a 10 00 addis r10,r10,4096 51d0: 55 29 02 06 rlwinm r9,r9,0,8,3 51d4: 7d 20 51 e4 mtsrin r9,r10 51d8: 3d 4a 10 00 addis r10,r10,4096 51dc: 39 29 01 11 addi r9,r9,273 51e0: 7c 08 50 40 cmplw r8,r10 51e4: 55 29 02 06 rlwinm r9,r9,0,8,3 51e8: 40 81 00 4c ble 5234 <perf_copy_attr+0x48c> 51ec: 7d 20 51 e4 mtsrin r9,r10 51f0: 39 29 01 11 addi r9,r9,273 51f4: 3c ea 10 00 addis r7,r10,4096 51f8: 55 29 02 06 rlwinm r9,r9,0,8,3 51fc: 7d 20 39 e4 mtsrin r9,r7 5200: 39 29 01 11 addi r9,r9,273 5204: 3c e7 10 00 addis r7,r7,4096 5208: 55 29 02 06 rlwinm r9,r9,0,8,3 520c: 7d 20 39 e4 mtsrin r9,r7 5210: 39 29 01 11 addi r9,r9,273 5214: 3c ea 30 00 addis r7,r10,12288 5218: 55 29 02 06 rlwinm r9,r9,0,8,3 521c: 7d 20 39 e4 mtsrin r9,r7 5220: 3d 4a 40 00 addis r10,r10,16384 5224: 39 29 01 11 addi r9,r9,273 5228: 7c 08 50 40 cmplw r8,r10 522c: 55 29 02 06 rlwinm r9,r9,0,8,3 5230: 41 81 ff bc bgt 51ec <perf_copy_attr+0x444> 5234: 4c 00 01 2c isync Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Export the ool handlers to fix build errors] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/d9121f96a7c4302946839a0771f5d1daeeb6968c.1622708530.git.christophe.leroy@csgroup.eu
| * | powerpc/32s: Allow disabling KUAP at boot timeChristophe Leroy2021-06-171-1/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PPC64 uses MMU features to enable/disable KUAP at boot time. But feature fixups are applied way too early on PPC32. Now that all KUAP related actions are in C following the conversion of KUAP initial setup and context switch in C, static branches can be used to enable/disable KUAP. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Export disable_kuap_key to fix build errors] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/cd79e8008455fba5395d099f9bb1305c039b931c.1622708530.git.christophe.leroy@csgroup.eu
| * | powerpc/32s: Allow disabling KUEP at boot timeChristophe Leroy2021-06-171-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PPC64 uses MMU features to enable/disable KUEP at boot time. But feature fixups are applied way too early on PPC32. Now that all KUEP related actions are in C following the conversion of KUEP initial setup and context switch in C, static branches can be used to enable/disable KUEP. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7745a2c3a08ec46302920a3f48d1cb9b5469dbbb.1622708530.git.christophe.leroy@csgroup.eu
| * | powerpc/32s: Simplify calculation of segment register contentChristophe Leroy2021-06-171-19/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | segment register has VSID on bits 8-31. Bits 4-7 are reserved, there is no requirement to set them to 0. VSIDs are calculated from VSID of SR0 by adding 0x111. Even with highest possible VSID which would be 0xFFFFF0, adding 16 times 0x111 results in 0x1001100. So, the reserved bits are never overflowed, no need to clear the reserved bits after each calculation. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/ddc1cfd2ec8f3b2395c6a4d7f2b0c1aa1b1e64fb.1622708530.git.christophe.leroy@csgroup.eu
| * | powerpc/32s: Convert switch_mmu_context() to CChristophe Leroy2021-06-171-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | switch_mmu_context() does things that can easily be done in C. For updating user segments, we have update_user_segments(). As mentionned in commit b5efec00b671 ("powerpc/32s: Move KUEP locking/unlocking in C"), update_user_segments() has the loop unrolled which is a significant performance gain. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/05c0875ad8220c03452c3a334946e207c6ca04d6.1622708530.git.christophe.leroy@csgroup.eu
| * | powerpc/32s: move CTX_TO_VSID() into mmu-hash.hChristophe Leroy2021-06-171-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to reuse it in switch_mmu_context(), this patch moves CTX_TO_VSID() macro into asm/book3s/32/mmu-hash.h Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/26b36ef2939234a04b37baf6ffe50cba81f5d1b7.1622708530.git.christophe.leroy@csgroup.eu
| * | powerpc/32s: Refactor update of user segment registersChristophe Leroy2021-06-172-0/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KUEP implements the update of user segment registers. Move it into mmu-hash.h in order to use it from other places. And inline kuep_lock() and kuep_unlock(). Inlining kuep_lock() is important for system_call_exception(), otherwise system_call_exception() has to save into stack the system call parameters that are used just after, and doing that takes more instructions than kuep_lock() itself. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/24591ca480d14a62ef910e38a5273d551262c4a2.1622708530.git.christophe.leroy@csgroup.eu
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