linux-dev/arch/powerpc/perf/callchain.c, branch linus/master

powerpc: make stack walking KASAN-safe

2021-06-16T14:09:11Z

Make our stack-walking code KASAN-safe by using __no_sanitize_address. Generic code, arm64, s390 and x86 all make accesses unchecked for similar sorts of reasons: when unwinding a stack, we might touch memory that KASAN has marked as being out-of-bounds. In ppc64 KASAN development, I hit this sometimes when checking for an exception frame - because we're checking an arbitrary offset into the stack frame. See commit 20955746320e ("s390/kasan: avoid false positives during stack unwind"), commit bcaf669b4bdb ("arm64: disable kasan when accessing frame->fp in unwind_frame"), commit 91e08ab0c851 ("x86/dumpstack: Prevent KASAN false positive warnings") and commit 6e22c8366416 ("tracing, kasan: Silence Kasan warning in check_stack of stack_tracer"). Signed-off-by: Daniel Axtens Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210614120907.1952321-1-dja@axtens.net

mm: don't include asm/pgtable.h if linux/mm.h is already included

2020-06-09T16:39:13Z

Patch series "mm: consolidate definitions of page table accessors", v2. The low level page table accessors (pXY_index(), pXY_offset()) are duplicated across all architectures and sometimes more than once. For instance, we have 31 definition of pgd_offset() for 25 supported architectures. Most of these definitions are actually identical and typically it boils down to, e.g. static inline unsigned long pmd_index(unsigned long address) { return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); } static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) { return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); } These definitions can be shared among 90% of the arches provided XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined. For architectures that really need a custom version there is always possibility to override the generic version with the usual ifdefs magic. These patches introduce include/linux/pgtable.h that replaces include/asm-generic/pgtable.h and add the definitions of the page table accessors to the new header. This patch (of 12): The linux/mm.h header includes to allow inlining of the functions involving page table manipulations, e.g. pte_alloc() and pmd_alloc(). So, there is no point to explicitly include in the files that include . The include statements in such cases are remove with a simple loop: for f in $(git grep -l "include ") ; do sed -i -e '/include / d' $f done Signed-off-by: Mike Rapoport Signed-off-by: Andrew Morton Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brian Cain Cc: Catalin Marinas Cc: Chris Zankel Cc: "David S. Miller" Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Greg Ungerer Cc: Guan Xuetao Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ley Foon Tan Cc: Mark Salter Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Mike Rapoport Cc: Nick Hu Cc: Paul Walmsley Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Tony Luck Cc: Vincent Chen Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org Signed-off-by: Linus Torvalds

powerpc/perf: split callchain.c by bitness

2020-04-02T13:10:00Z

Building callchain.c with !COMPAT proved quite ugly with all the defines. Splitting out the 32bit and 64bit parts looks better. No code change intended. Signed-off-by: Michal Suchanek Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/a20027bf1074935a7934ee2a6757c99ea047e70d.1584699455.git.msuchanek@suse.de

powerpc/64: make buildable without CONFIG_COMPAT

2020-04-02T13:10:00Z

There are numerous references to 32bit functions in generic and 64bit code so ifdef them out. Signed-off-by: Michal Suchanek Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/e5619617020ef3a1f54f0c076e7d74cb9ec9f3bf.1584699455.git.msuchanek@suse.de

powerpc/perf: consolidate valid_user_sp -> invalid_user_sp

2020-04-02T13:10:00Z

Merge the 32bit and 64bit version. Halve the check constants on 32bit. Use STACK_TOP since it is defined. Passing is_64 is now redundant since is_32bit_task() is used to determine which callchain variant should be used. Use STACK_TOP and is_32bit_task() directly. This removes a page from the valid 32bit area on 64bit: #define TASK_SIZE_USER32 (0x0000000100000000UL - (1 * PAGE_SIZE)) #define STACK_TOP_USER32 TASK_SIZE_USER32 Change return value to bool. It is inverted by users anyway. Change to invalid_user_sp to avoid inverting the return value twice. Signed-off-by: Michal Suchanek Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/be8e40fc0737fb28ad08b198552dee7cac1c5ce2.1584699455.git.msuchanek@suse.de

powerpc/perf: consolidate read_user_stack_32

2020-04-02T13:09:59Z

There are two almost identical copies for 32bit and 64bit. The function is used only in 32bit code which will be split out in next patch so consolidate to one function. Signed-off-by: Michal Suchanek Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/0c21c919ed1296420199c78f7c3cfd29d3c7e909.1584699455.git.msuchanek@suse.de

powerpc: use probe_user_read() and probe_user_write()

2020-01-25T13:11:35Z

Instead of opencoding, use probe_user_read() to failessly read a user location and probe_user_write() for writing to user. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/e041f5eedb23f09ab553be8a91c3de2087147320.1579800517.git.christophe.leroy@c-s.fr

powerpc/perf: remove current_is_64bit()

2019-11-13T05:58:10Z

Since commit ed1cd6deb013 ("powerpc: Activate CONFIG_THREAD_INFO_IN_TASK") current_is_64bit() is quivalent to !is_32bit_task(). Remove the redundant function. Suggested-by: Christophe Leroy Signed-off-by: Michal Suchanek Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190912194633.12045-1-msuchanek@suse.de

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/mm: Rename find_linux_pte_or_hugepte()

2017-08-17T13:13:46Z

Add newer helpers to make the function usage simpler. It is always recommended to use find_current_mm_pte() for walking the page table. If we cannot use find_current_mm_pte(), it should be documented why the said usage of __find_linux_pte() is safe against a parallel THP split. For now we have KVM code using __find_linux_pte(). This is because kvm code ends up calling __find_linux_pte() in real mode with MSR_EE=0 but with PACA soft_enabled = 1. We may want to fix that later and make sure we keep the MSR_EE and PACA soft_enabled in sync. When we do that we can switch kvm to use find_linux_pte(). Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman