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* Merge branch 'akpm' (patches from Andrew)Linus Torvalds2020-08-0719-21/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc updates from Andrew Morton: - a few MM hotfixes - kthread, tools, scripts, ntfs and ocfs2 - some of MM Subsystems affected by this patch series: kthread, tools, scripts, ntfs, ocfs2 and mm (hofixes, pagealloc, slab-generic, slab, slub, kcsan, debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, mincore, sparsemem, vmalloc, kasan, pagealloc, hugetlb and vmscan). * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits) mm: vmscan: consistent update to pgrefill mm/vmscan.c: fix typo khugepaged: khugepaged_test_exit() check mmget_still_valid() khugepaged: retract_page_tables() remember to test exit khugepaged: collapse_pte_mapped_thp() protect the pmd lock khugepaged: collapse_pte_mapped_thp() flush the right range mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possible mm: thp: replace HTTP links with HTTPS ones mm/page_alloc: fix memalloc_nocma_{save/restore} APIs mm/page_alloc.c: skip setting nodemask when we are in interrupt mm/page_alloc: fallbacks at most has 3 elements mm/page_alloc: silence a KASAN false positive mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask() mm/page_alloc.c: simplify pageblock bitmap access mm/page_alloc.c: extract the common part in pfn_to_bitidx() mm/page_alloc.c: replace the definition of NR_MIGRATETYPE_BITS with PB_migratetype_bits mm/shuffle: remove dynamic reconfiguration mm/memory_hotplug: document why shuffle_zone() is relevant mm/page_alloc: remove nr_free_pagecache_pages() mm: remove vm_total_pages ...
| * mm/sparse: cleanup the code surrounding memory_present()Mike Rapoport2020-08-072-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After removal of CONFIG_HAVE_MEMBLOCK_NODE_MAP we have two equivalent functions that call memory_present() for each region in memblock.memory: sparse_memory_present_with_active_regions() and membocks_present(). Moreover, all architectures have a call to either of these functions preceding the call to sparse_init() and in the most cases they are called one after the other. Mark the regions from memblock.memory as present during sparce_init() by making sparse_init() call memblocks_present(), make memblocks_present() and memory_present() functions static and remove redundant sparse_memory_present_with_active_regions() function. Also remove no longer required HAVE_MEMORY_PRESENT configuration option. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200712083130.22919-1-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * mm/sparsemem: enable vmem_altmap support in vmemmap_alloc_block_buf()Anshuman Khandual2020-08-071-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are many instances where vmemap allocation is often switched between regular memory and device memory just based on whether altmap is available or not. vmemmap_alloc_block_buf() is used in various platforms to allocate vmemmap mappings. Lets also enable it to handle altmap based device memory allocation along with existing regular memory allocations. This will help in avoiding the altmap based allocation switch in many places. To summarize there are two different methods to call vmemmap_alloc_block_buf(). vmemmap_alloc_block_buf(size, node, NULL) /* Allocate from system RAM */ vmemmap_alloc_block_buf(size, node, altmap) /* Allocate from altmap */ This converts altmap_alloc_block_buf() into a static function, drops it's entry from the header and updates Documentation/vm/memory-model.rst. Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Jia He <justin.he@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Will Deacon <will@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Hsin-Yi Wang <hsinyi@chromium.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Steve Capper <steve.capper@arm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Yu Zhao <yuzhao@google.com> Link: http://lkml.kernel.org/r/1594004178-8861-3-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * mm: remove unneeded includes of <asm/pgalloc.h>Mike Rapoport2020-08-0717-16/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "mm: cleanup usage of <asm/pgalloc.h>" Most architectures have very similar versions of pXd_alloc_one() and pXd_free_one() for intermediate levels of page table. These patches add generic versions of these functions in <asm-generic/pgalloc.h> and enable use of the generic functions where appropriate. In addition, functions declared and defined in <asm/pgalloc.h> headers are used mostly by core mm and early mm initialization in arch and there is no actual reason to have the <asm/pgalloc.h> included all over the place. The first patch in this series removes unneeded includes of <asm/pgalloc.h> In the end it didn't work out as neatly as I hoped and moving pXd_alloc_track() definitions to <asm-generic/pgalloc.h> would require unnecessary changes to arches that have custom page table allocations, so I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local to mm/. This patch (of 8): In most cases <asm/pgalloc.h> header is required only for allocations of page table memory. Most of the .c files that include that header do not use symbols declared in <asm/pgalloc.h> and do not require that header. As for the other header files that used to include <asm/pgalloc.h>, it is possible to move that include into the .c file that actually uses symbols from <asm/pgalloc.h> and drop the include from the header file. The process was somewhat automated using sed -i -E '/[<"]asm\/pgalloc\.h/d' \ $(grep -L -w -f /tmp/xx \ $(git grep -E -l '[<"]asm/pgalloc\.h')) where /tmp/xx contains all the symbols defined in arch/*/include/asm/pgalloc.h. [rppt@linux.ibm.com: fix powerpc warning] Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Joerg Roedel <joro@8bytes.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Cc: Stafford Horne <shorne@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Joerg Roedel <jroedel@suse.de> Cc: Matthew Wilcox <willy@infradead.org> Link: http://lkml.kernel.org/r/20200627143453.31835-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200627143453.31835-2-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'powerpc-5.9-1' of ↵Linus Torvalds2020-08-0719-953/+572
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Add support for (optionally) using queued spinlocks & rwlocks. - Support for a new faster system call ABI using the scv instruction on Power9 or later. - Drop support for the PROT_SAO mmap/mprotect flag as it will be unsupported on Power10 and future processors, leaving us with no way to implement the functionality it requests. This risks breaking userspace, though we believe it is unused in practice. - A bug fix for, and then the removal of, our custom stack expansion checking. We now allow stack expansion up to the rlimit, like other architectures. - Remove the remnants of our (previously disabled) topology update code, which tried to react to NUMA layout changes on virtualised systems, but was prone to crashes and other problems. - Add PMU support for Power10 CPUs. - A change to our signal trampoline so that we don't unbalance the link stack (branch return predictor) in the signal delivery path. - Lots of other cleanups, refactorings, smaller features and so on as usual. Thanks to: Abhishek Goel, Alastair D'Silva, Alexander A. Klimov, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Balamuruhan S, Bharata B Rao, Bill Wendling, Bin Meng, Cédric Le Goater, Chris Packham, Christophe Leroy, Christoph Hellwig, Daniel Axtens, Dan Williams, David Lamparter, Desnes A. Nunes do Rosario, Erhard F., Finn Thain, Frederic Barrat, Ganesh Goudar, Gautham R. Shenoy, Geoff Levand, Greg Kurz, Gustavo A. R. Silva, Hari Bathini, Harish, Imre Kaloz, Joel Stanley, Joe Perches, John Crispin, Jordan Niethe, Kajol Jain, Kamalesh Babulal, Kees Cook, Laurent Dufour, Leonardo Bras, Li RongQing, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Cave-Ayland, Michal Suchanek, Milton Miller, Mimi Zohar, Murilo Opsfelder Araujo, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Oliver O'Halloran, Palmer Dabbelt, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud, Pingfan Liu, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Randy Dunlap, Ravi Bangoria, Sachin Sant, Sam Bobroff, Sandipan Das, Santosh Sivaraj, Satheesh Rajendran, Shirisha Ganta, Sourabh Jain, Srikar Dronamraju, Stan Johnson, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thiago Jung Bauermann, Tom Lane, Vaibhav Jain, Vladis Dronov, Wei Yongjun, Wen Xiong, YueHaibing. * tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (337 commits) selftests/powerpc: Fix pkey syscall redefinitions powerpc: Fix circular dependency between percpu.h and mmu.h powerpc/powernv/sriov: Fix use of uninitialised variable selftests/powerpc: Skip vmx/vsx/tar/etc tests on older CPUs powerpc/40x: Fix assembler warning about r0 powerpc/papr_scm: Add support for fetching nvdimm 'fuel-gauge' metric powerpc/papr_scm: Fetch nvdimm performance stats from PHYP cpuidle: pseries: Fixup exit latency for CEDE(0) cpuidle: pseries: Add function to parse extended CEDE records cpuidle: pseries: Set the latency-hint before entering CEDE selftests/powerpc: Fix online CPU selection powerpc/perf: Consolidate perf_callchain_user_[64|32]() powerpc/pseries/hotplug-cpu: Remove double free in error path powerpc/pseries/mobility: Add pr_debug() for device tree changes powerpc/pseries/mobility: Set pr_fmt() powerpc/cacheinfo: Warn if cache object chain becomes unordered powerpc/cacheinfo: Improve diagnostics about malformed cache lists powerpc/cacheinfo: Use name@unit instead of full DT path in debug messages powerpc/cacheinfo: Set pr_fmt() powerpc: fix function annotations to avoid section mismatch warnings with gcc-10 ...
| * powerpc: fix function annotations to avoid section mismatch warnings with gcc-10Vladis Dronov2020-07-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Certain warnings are emitted for powerpc code when building with a gcc-10 toolset: WARNING: modpost: vmlinux.o(.text.unlikely+0x377c): Section mismatch in reference from the function remove_pmd_table() to the function .meminit.text:split_kernel_mapping() The function remove_pmd_table() references the function __meminit split_kernel_mapping(). This is often because remove_pmd_table lacks a __meminit annotation or the annotation of split_kernel_mapping is wrong. Add the appropriate __init and __meminit annotations to make modpost not complain. In all the cases there are just a single callsite from another __init or __meminit function: __meminit remove_pagetable() -> remove_pud_table() -> remove_pmd_table() __init prom_init() -> setup_secure_guest() __init xive_spapr_init() -> xive_spapr_disabled() Signed-off-by: Vladis Dronov <vdronov@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200729133741.62789-1-vdronov@redhat.com
| * powerpc/drmem: Make LMB walk a bit more flexibleHari Bathini2020-07-292-35/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, numa & prom are the only users of drmem LMB walk code. Loading kdump with kexec_file also needs to walk the drmem LMBs to setup the usable memory ranges for kdump kernel. But there are couple of issues in using the code as is. One, walk_drmem_lmb() code is built into the .init section currently, while kexec_file needs it later. Two, there is no scope to pass data to the callback function for processing and/or erroring out on certain conditions. Fix that by, moving drmem LMB walk code out of .init section, adding scope to pass data to the callback function and bailing out when an error is encountered in the callback function. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Tested-by: Pingfan Liu <piliu@redhat.com> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/159602282727.575379.3979857013827701828.stgit@hbathini
| * powerpc/book3s64/radix: Add kernel command line option to disable radix GTSEAneesh Kumar K.V2020-07-291-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a kernel command line option that can be used to disable GTSE support. Disabling GTSE implies kernel will make hcalls to invalidate TLB entries. This was done so that we can do VM migration between configs that enable/disable GTSE support via hypervisor. To migrate a VM from a system that supports GTSE to a system that doesn't, we can boot the guest with radix_hcall_invalidate=on, thereby forcing the guest to use hcalls for TLB invalidates. The check for hcall availability is done in pSeries_setup_arch so that the panic message appears on the console. This should only happen on a hypervisor that doesn't force the guest to hash translation even though it can't handle the radix GTSE=0 request via CAS. With radix_hcall_invalidate=on if the hypervisor doesn't support hcall_rpt_invalidate hcall it should force the LPAR to hash translation. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200727085908.420806-1-aneesh.kumar@linux.ibm.com
| * powerpc/hugetlb/cma: Allocate gigantic hugetlb pages using CMAAneesh Kumar K.V2020-07-291-0/+18
| | | | | | | | | | | | | | | | | | | | commit: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma") added support for allocating gigantic hugepages using CMA. This patch enables the same for powerpc Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200713150749.25245-1-aneesh.kumar@linux.ibm.com
| * powerpc/64e: Drop dead BOOK3E_MMU_TLB_STATS codeMichael Ellerman2020-07-291-44/+3
| | | | | | | | | | | | | | | | | | | | This code was merged 11 years ago in commit 13363ab9b9d0 ("powerpc: Add definitions used by exception handling on 64-bit Book3E") but was never able to be built because CONFIG_BOOK3E_MMU_TLB_STATS never existed. Remove it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200724131728.1643966-4-mpe@ellerman.id.au
| * powerpc/mm: Limit resize_hpt_for_hotplug() call to hash guests onlyBharata B Rao2020-07-292-6/+7
| | | | | | | | | | | | | | | | | | | | | | | | During memory hotplug and unplug, resize_hpt_for_hotplug() gets called for both hash and radix guests but it should be called only for hash guests. Though the call does nothing in the radix guest case, it is cleaner to push this call into hash specific memory hotplug routines. Reported-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200727095704.1432916-1-bharata@linux.ibm.com
| * powerpc/mm: Remove custom stack expansion checkingMichael Ellerman2020-07-291-104/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have powerpc specific logic in our page fault handling to decide if an access to an unmapped address below the stack pointer should expand the stack VMA. The logic aims to prevent userspace from doing bad accesses below the stack pointer. However as long as the stack is < 1MB in size, we allow all accesses without further checks. Adding some debug I see that I can do a full kernel build and LTP run, and not a single process has used more than 1MB of stack. So for the majority of processes the logic never even fires. We also recently found a nasty bug in this code which could cause userspace programs to be killed during signal delivery. It went unnoticed presumably because most processes use < 1MB of stack. The generic mm code has also grown support for stack guard pages since this code was originally written, so the most heinous case of the stack expanding into other mappings is now handled for us. Finally although some other arches have special logic in this path, from what I can tell none of x86, arm64, arm and s390 impose any extra checks other than those in expand_stack(). So drop our complicated logic and like other architectures just let the stack expand as long as its within the rlimit. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Tested-by: Daniel Axtens <dja@axtens.net> Link: https://lore.kernel.org/r/20200724092528.1578671-4-mpe@ellerman.id.au
| * powerpc: Allow 4224 bytes of stack expansion for the signal frameMichael Ellerman2020-07-291-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have powerpc specific logic in our page fault handling to decide if an access to an unmapped address below the stack pointer should expand the stack VMA. The code was originally added in 2004 "ported from 2.4". The rough logic is that the stack is allowed to grow to 1MB with no extra checking. Over 1MB the access must be within 2048 bytes of the stack pointer, or be from a user instruction that updates the stack pointer. The 2048 byte allowance below the stack pointer is there to cover the 288 byte "red zone" as well as the "about 1.5kB" needed by the signal delivery code. Unfortunately since then the signal frame has expanded, and is now 4224 bytes on 64-bit kernels with transactional memory enabled. This means if a process has consumed more than 1MB of stack, and its stack pointer lies less than 4224 bytes from the next page boundary, signal delivery will fault when trying to expand the stack and the process will see a SEGV. The total size of the signal frame is the size of struct rt_sigframe (which includes the red zone) plus __SIGNAL_FRAMESIZE (128 bytes on 64-bit). The 2048 byte allowance was correct until 2008 as the signal frame was: struct rt_sigframe { struct ucontext uc; /* 0 1440 */ /* --- cacheline 11 boundary (1408 bytes) was 32 bytes ago --- */ long unsigned int _unused[2]; /* 1440 16 */ unsigned int tramp[6]; /* 1456 24 */ struct siginfo * pinfo; /* 1480 8 */ void * puc; /* 1488 8 */ struct siginfo info; /* 1496 128 */ /* --- cacheline 12 boundary (1536 bytes) was 88 bytes ago --- */ char abigap[288]; /* 1624 288 */ /* size: 1920, cachelines: 15, members: 7 */ /* padding: 8 */ }; 1920 + 128 = 2048 Then in commit ce48b2100785 ("powerpc: Add VSX context save/restore, ptrace and signal support") (Jul 2008) the signal frame expanded to 2304 bytes: struct rt_sigframe { struct ucontext uc; /* 0 1696 */ <-- /* --- cacheline 13 boundary (1664 bytes) was 32 bytes ago --- */ long unsigned int _unused[2]; /* 1696 16 */ unsigned int tramp[6]; /* 1712 24 */ struct siginfo * pinfo; /* 1736 8 */ void * puc; /* 1744 8 */ struct siginfo info; /* 1752 128 */ /* --- cacheline 14 boundary (1792 bytes) was 88 bytes ago --- */ char abigap[288]; /* 1880 288 */ /* size: 2176, cachelines: 17, members: 7 */ /* padding: 8 */ }; 2176 + 128 = 2304 At this point we should have been exposed to the bug, though as far as I know it was never reported. I no longer have a system old enough to easily test on. Then in 2010 commit 320b2b8de126 ("mm: keep a guard page below a grow-down stack segment") caused our stack expansion code to never trigger, as there was always a VMA found for a write up to PAGE_SIZE below r1. That meant the bug was hidden as we continued to expand the signal frame in commit 2b0a576d15e0 ("powerpc: Add new transactional memory state to the signal context") (Feb 2013): struct rt_sigframe { struct ucontext uc; /* 0 1696 */ /* --- cacheline 13 boundary (1664 bytes) was 32 bytes ago --- */ struct ucontext uc_transact; /* 1696 1696 */ <-- /* --- cacheline 26 boundary (3328 bytes) was 64 bytes ago --- */ long unsigned int _unused[2]; /* 3392 16 */ unsigned int tramp[6]; /* 3408 24 */ struct siginfo * pinfo; /* 3432 8 */ void * puc; /* 3440 8 */ struct siginfo info; /* 3448 128 */ /* --- cacheline 27 boundary (3456 bytes) was 120 bytes ago --- */ char abigap[288]; /* 3576 288 */ /* size: 3872, cachelines: 31, members: 8 */ /* padding: 8 */ /* last cacheline: 32 bytes */ }; 3872 + 128 = 4000 And commit 573ebfa6601f ("powerpc: Increase stack redzone for 64-bit userspace to 512 bytes") (Feb 2014): struct rt_sigframe { struct ucontext uc; /* 0 1696 */ /* --- cacheline 13 boundary (1664 bytes) was 32 bytes ago --- */ struct ucontext uc_transact; /* 1696 1696 */ /* --- cacheline 26 boundary (3328 bytes) was 64 bytes ago --- */ long unsigned int _unused[2]; /* 3392 16 */ unsigned int tramp[6]; /* 3408 24 */ struct siginfo * pinfo; /* 3432 8 */ void * puc; /* 3440 8 */ struct siginfo info; /* 3448 128 */ /* --- cacheline 27 boundary (3456 bytes) was 120 bytes ago --- */ char abigap[512]; /* 3576 512 */ <-- /* size: 4096, cachelines: 32, members: 8 */ /* padding: 8 */ }; 4096 + 128 = 4224 Then finally in 2017, commit 1be7107fbe18 ("mm: larger stack guard gap, between vmas") exposed us to the existing bug, because it changed the stack VMA to be the correct/real size, meaning our stack expansion code is now triggered. Fix it by increasing the allowance to 4224 bytes. Hard-coding 4224 is obviously unsafe against future expansions of the signal frame in the same way as the existing code. We can't easily use sizeof() because the signal frame structure is not in a header. We will either fix that, or rip out all the custom stack expansion checking logic entirely. Fixes: ce48b2100785 ("powerpc: Add VSX context save/restore, ptrace and signal support") Cc: stable@vger.kernel.org # v2.6.27+ Reported-by: Tom Lane <tgl@sss.pgh.pa.us> Tested-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200724092528.1578671-2-mpe@ellerman.id.au
| * powerpc/ptdump: Refactor update of pg_stateChristophe Leroy2020-07-261-14/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In note_page(), the pg_state is updated the same way in two places. Add note_page_update_state() to do it. Also include the display of boundary markers there as it is missing "no level" leg, leading to a mismatch when the first two markers are at the same address and the first displayed area uses that address. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/a284a809f01c705bbaab303b06fda216f147a99a.1593429426.git.christophe.leroy@csgroup.eu
| * powerpc/ptdump: Refactor update of st->last_paChristophe Leroy2020-07-261-4/+1
| | | | | | | | | | | | | | | | | | st->last_pa is always updated in note_page() so it can be done outside the if/elseif/else block. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/610d6b1a60ad0bedef865a90153c1110cfaa507e.1593429426.git.christophe.leroy@csgroup.eu
| * powerpc/32s: Use dedicated segment for modules with STRICT_KERNEL_RWXChristophe Leroy2020-07-261-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | When STRICT_KERNEL_RWX is set, we want to set NX bit on vmalloc segments. But modules require exec. Use a dedicated segment for modules. There is not much space above kernel, and we don't waste vmalloc space to do alignment. Therefore, we take the segment before PAGE_OFFSET for modules. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/eb8faba9148b6cf17c696ba776b4e8ee2f6313bf.1593428200.git.christophe.leroy@csgroup.eu
| * powerpc/32s: Kernel space starts at TASK_SIZEChristophe Leroy2020-07-261-1/+1
| | | | | | | | | | | | | | | | | | Kernel space starts at TASK_SIZE. Select kernel page table when address is over TASK_SIZE. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/893425e32cd0a003539573b2d115e0ffa98bc26c.1593428200.git.christophe.leroy@csgroup.eu
| * powerpc/32: Set user/kernel boundary at TASK_SIZE instead of PAGE_OFFSETChristophe Leroy2020-07-261-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | User space stops at TASK_SIZE. At the moment, kernel space starts at PAGE_OFFSET. In order to use space between TASK_SIZE and PAGE_OFFSET for modules, make TASK_SIZE the limit between user and kernel space. Note that fault.c already considers TASK_SIZE as the boundary between user and kernel space. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/b38b52cd8dabbb56fbd6f9219d6f3cdccbb43b44.1593428200.git.christophe.leroy@csgroup.eu
| * powerpc/32s: Only leave NX unset on segments used for modulesChristophe Leroy2020-07-261-3/+14
| | | | | | | | | | | | | | | | | | | | Instead of leaving NX unset on all segments above the start of vmalloc space, only leave NX unset on segments used for modules. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7172c0f5253419315e434a1816ee3d6ed6505bc0.1593428200.git.christophe.leroy@csgroup.eu
| * powerpc: Use MODULES_VADDR if definedChristophe Leroy2020-07-261-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | In order to allow allocation of modules outside of vmalloc space, use MODULES_VADDR and MODULES_END when MODULES_VADDR is defined. Redefine module_alloc() when MODULES_VADDR defined. Unmap corresponding KASAN shadow memory. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/7ecf5fff1eef67d450e73fc412b6ec3818483d75.1593428200.git.christophe.leroy@csgroup.eu
| * powerpc/numa: Limit possible nodes to within num_possible_nodesSrikar Dronamraju2020-07-261-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | MAX_NUMNODES is a theoretical maximum number of nodes thats is supported by the kernel. Device tree properties exposes the number of possible nodes on the current platform. The kernel would detected this and would use it for most of its resource allocations. If the platform now increases the nodes to over what was already exposed, then it may lead to inconsistencies. Hence limit it to the already exposed nodes. Suggested-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200724105809.24733-1-srikar@linux.vnet.ibm.com
| * powerpc/book3s64/pkey: Disable pkey on POWER6 and beforeAneesh Kumar K.V2020-07-261-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | POWER6 only supports AMR update via privileged mode (MSR[PR] = 0, SPRN_AMR=29) The PR=1 (userspace) alias for that SPR (SPRN_AMR=13) was only supported from POWER7. Since we don't allow userspace modifying of AMR value we should disable pkey support on P6 and before. The hypervisor will still report pkey support via "ibm,processor-storage-keys". Hence also check for P7 CPU_FTR bit to decide on pkey support. Fixes: f491fe3fb41e ("powerpc/book3s64/pkeys: Simplify the key initialization") Reported-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200726132517.399076-1-aneesh.kumar@linux.ibm.com
| * powerpc/mm/hash64: Remove comment that is no longer validSantosh Sivaraj2020-07-231-4/+0
| | | | | | | | | | | | | | | | | | | | | | hash_low_64.S was removed in commit a43c0eb8364c ("powerpc/mm: Convert 4k insert from asm to C") and flush_hash_page() is no longer called from any assembly routine. Signed-off-by: Santosh Sivaraj <santosh@fossix.org> [mpe: Tweak comment wording] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200721091915.205006-1-santosh@fossix.org
| * powerpc/64s: Remove PROT_SAO supportNicholas Piggin2020-07-211-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ISA v3.1 does not support the SAO storage control attribute required to implement PROT_SAO. PROT_SAO was used by specialised system software (Lx86) that has been discontinued for about 7 years, and is not thought to be used elsewhere, so removal should not cause problems. We rather remove it than keep support for older processors, because live migrating guest partitions to newer processors may not be possible if SAO is in use (or worse allowed with silent races). - PROT_SAO stays in the uapi header so code using it would still build. - arch_validate_prot() is removed, the generic version rejects PROT_SAO so applications would get a failure at mmap() time. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Drop KVM change for the time being] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200703011958.1166620-3-npiggin@gmail.com
| * powerpc/book3s64/pkeys: Remove is_pkey_enabled()Aneesh Kumar K.V2020-07-211-20/+11
| | | | | | | | | | | | | | | | | | | | | | There is only one caller to this function and the function is wrongly named. Avoid further confusion w.r.t name and open code this at the only call site. Also remove read_uamor(). There are no users for the same after this. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-24-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/kuap: Move UAMOR setup to key init functionAneesh Kumar K.V2020-07-203-17/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | UAMOR values are not application-specific. The kernel initializes its value based on different reserved keys. Remove the thread-specific UAMOR value and don't switch the UAMOR on context switch. Move UAMOR initialization to key initialization code and remove thread_struct.uamor because it is not used anymore. Before commit: 4a4a5e5d2aad ("powerpc/pkeys: key allocation/deallocation must not change pkey registers") we used to update uamor based on key allocation and free. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-20-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/keys/kuap: Reset AMR/IAMR values on kexecAneesh Kumar K.V2020-07-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As we kexec across kernels that use AMR/IAMR for different purposes we need to ensure that new kernels get kexec'd with a reset value of AMR/IAMR. For ex: the new kernel can use key 0 for kernel mapping and the old AMR value prevents access to key 0. This patch also removes reset if IAMR and AMOR in kexec_sequence. Reset of AMOR is not needed and the IAMR reset is partial (it doesn't do the reset on secondary cpus) and is redundant with this patch. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-19-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/keys: Print information during boot.Aneesh Kumar K.V2020-07-201-0/+1
| | | | | | | | | | | | Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-18-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Use MMU_FTR_PKEY instead of pkey_disabled static keyAneesh Kumar K.V2020-07-201-10/+7
| | | | | | | | | | | | | | | | Instead of pkey_disabled static key use mmu feature MMU_FTR_PKEY. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-17-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Use pkey_execute_disable_supportedAneesh Kumar K.V2020-07-201-3/+3
| | | | | | | | | | | | | | | | | | Use pkey_execute_disable_supported to check for execute key support instead of pkey_disabled. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-16-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/kuep: Add MMU_FTR_KUEPAneesh Kumar K.V2020-07-201-1/+3
| | | | | | | | | | | | | | | | | | This will be used to enable/disable Kernel Userspace Execution Prevention (KUEP). Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-15-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Add MMU_FTR_PKEYAneesh Kumar K.V2020-07-201-22/+30
| | | | | | | | | | | | | | | | | | | | | | | | Parse storage keys related device tree entry in early_init_devtree and enable MMU feature MMU_FTR_PKEY if pkeys are supported. MMU feature is used instead of CPU feature because this enables us to group MMU_FTR_KUAP and MMU_FTR_PKEY in asm feature fixup code. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-14-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Mark all the pkeys above max pkey as reservedAneesh Kumar K.V2020-07-201-2/+3
| | | | | | | | | | | | | | | | | | | | | | The hypervisor can return less than max allowed pkey (for ex: 31) instead of 32. We should mark all the pkeys above max allowed as reserved so that we avoid the allocation of the wrong pkey(for ex: key 31 in the above case) by userspace. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-13-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Make initial_allocation_mask staticAneesh Kumar K.V2020-07-201-2/+5
| | | | | | | | | | | | | | | | | | initial_allocation_mask is not used outside this file. Also mark reserved_allocation_mask and initial_allocation_mask __ro_after_init; Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-12-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Convert pkey_total to num_pkeyAneesh Kumar K.V2020-07-201-7/+7
| | | | | | | | | | | | | | | | | | num_pkey now represents max number of keys supported such that we return to userspace 0 - num_pkey - 1. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-11-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Simplify pkey disable branchAneesh Kumar K.V2020-07-201-4/+3
| | | | | | | | | | | | | | | | | | Make the default value FALSE (pkey enabled) and set to TRUE when we find the total number of keys supported to be zero. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-10-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Prevent key 1 modification from userspace.Aneesh Kumar K.V2020-07-201-0/+1
| | | | | | | | | | | | | | | | | | Key 1 is marked reserved by ISA. Setup uamor to prevent userspace modification of the same. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-8-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Simplify the key initializationAneesh Kumar K.V2020-07-201-83/+116
| | | | | | | | | | | | | | | | | | | | | | Add documentation explaining the execute_only_key. The reservation and initialization mask details are also explained in this patch. No functional change in this patch. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-7-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Explain key 1 reservation detailsAneesh Kumar K.V2020-07-201-1/+4
| | | | | | | | | | | | | | | | This explains the details w.r.t key 1. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-6-aneesh.kumar@linux.ibm.com
| * powerpc/book3s64/pkeys: Use PVR check instead of cpu featureAneesh Kumar K.V2020-07-201-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | We are wrongly using CPU_FTRS_POWER8 to check for P8 support. Instead, we should use PVR value. Now considering we are using CPU_FTRS_POWER8, that implies we returned true for P9 with older firmware. Keep the same behavior by checking for P9 PVR value. Fixes: cf43d3b26452 ("powerpc: Enable pkey subsystem") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709032946.881753-2-aneesh.kumar@linux.ibm.com
| * powerpc/mm/radix: Create separate mappings for hot-plugged memoryAneesh Kumar K.V2020-07-201-11/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To enable memory unplug without splitting kernel page table mapping, we force the max mapping size to the LMB size. LMB size is the unit in which hypervisor will do memory add/remove operation. Pseries systems supports max LMB size of 256MB. Hence on pseries, we now end up mapping memory with 2M page size instead of 1G. To improve that we want hypervisor to hint the kernel about the hotplug memory range. That was added that as part of commit b6eca183e23e ("powerpc/kernel: Enables memory hot-remove after reboot on pseries guests") But PowerVM doesn't provide that hint yet. Once we get PowerVM updated, we can then force the 2M mapping only to hot-pluggable memory region using memblock_is_hotpluggable(). Till then let's depend on LMB size for finding the mapping page size for linear range. With this change KVM guest will also be doing linear mapping with 2M page size. The actual TLB benefit of mapping guest page table entries with hugepage size can only be materialized if the partition scoped entries are also using the same or higher page size. A guest using 1G hugetlbfs backing guest memory can have a performance impact with the above change. Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> [mpe: Fold in fix from Aneesh spotted by lkp@intel.com] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709131925.922266-5-aneesh.kumar@linux.ibm.com
| * powerpc/mm/radix: Remove split_kernel_mapping()Bharata B Rao2020-07-201-76/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We split the page table mapping on memory unplug if the linear range was mapped with huge page mapping (for ex: 1G) The page table splitting code has a few issues: 1. Recursive locking -------------------- Memory unplug path takes cpu_hotplug_lock and calls stop_machine() for splitting the mappings. However stop_machine() takes cpu_hotplug_lock again causing deadlock. 2. BUG: sleeping function called from in_atomic() context --------------------------------------------------------- Memory unplug path (remove_pagetable) takes init_mm.page_table_lock spinlock and later calls stop_machine() which does wait_for_completion() 3. Bad unlock unbalance ----------------------- Memory unplug path takes init_mm.page_table_lock spinlock and calls stop_machine(). The stop_machine thread function runs in a different thread context (migration thread) which tries to release and reaquire ptl. Releasing ptl from a different thread than which acquired it causes bad unlock unbalance. These problems can be avoided if we avoid mapping hot-plugged memory with 1G mapping, thereby removing the need for splitting them during unplug. The kernel always make sure the minimum unplug request is SUBSECTION_SIZE for device memory and SECTION_SIZE for regular memory. In preparation for such a change remove page table splitting support. This essentially is a revert of commit 4dd5f8a99e791 ("powerpc/mm/radix: Split linear mapping on hot-unplug") Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709131925.922266-4-aneesh.kumar@linux.ibm.com
| * powerpc/mm/radix: Free PUD table when freeing pagetableBharata B Rao2020-07-201-0/+16
| | | | | | | | | | | | | | | | | | | | | | remove_pagetable() isn't freeing PUD table. This causes memory leak during memory unplug. Fix this. Fixes: 4b5d62ca17a1 ("powerpc/mm: add radix__remove_section_mapping()") Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709131925.922266-3-aneesh.kumar@linux.ibm.com
| * powerpc/mm/radix: Fix PTE/PMD fragment count for early page table mappingsAneesh Kumar K.V2020-07-203-5/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can hit the following BUG_ON during memory unplug: kernel BUG at arch/powerpc/mm/book3s64/pgtable.c:342! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries NIP [c000000000093308] pmd_fragment_free+0x48/0xc0 LR [c00000000147bfec] remove_pagetable+0x578/0x60c Call Trace: 0xc000008050000000 (unreliable) remove_pagetable+0x384/0x60c radix__remove_section_mapping+0x18/0x2c remove_section_mapping+0x1c/0x3c arch_remove_memory+0x11c/0x180 try_remove_memory+0x120/0x1b0 __remove_memory+0x20/0x40 dlpar_remove_lmb+0xc0/0x114 dlpar_memory+0x8b0/0xb20 handle_dlpar_errorlog+0xc0/0x190 pseries_hp_work_fn+0x2c/0x60 process_one_work+0x30c/0x810 worker_thread+0x98/0x540 kthread+0x1c4/0x1d0 ret_from_kernel_thread+0x5c/0x74 This occurs when unplug is attempted for such memory which has been mapped using memblock pages as part of early kernel page table setup. We wouldn't have initialized the PMD or PTE fragment count for those PMD or PTE pages. This can be fixed by allocating memory in PAGE_SIZE granularity during early page table allocation. This makes sure a specific page is not shared for another memblock allocation and we can free them correctly on removing page-table pages. Since we now do PAGE_SIZE allocations for both PUD table and PMD table (Note that PTE table allocation is already of PAGE_SIZE), we end up allocating more memory for the same amount of system RAM. Here is a comparision of how much more we need for a 64T and 2G system after this patch: 1. 64T system ------------- 64T RAM would need 64G for vmemmap with struct page size being 64B. 128 PUD tables for 64T memory (1G mappings) 1 PUD table and 64 PMD tables for 64G vmemmap (2M mappings) With default PUD[PMD]_TABLE_SIZE(4K), (128+1+64)*4K=772K With PAGE_SIZE(64K) table allocations, (128+1+64)*64K=12352K 2. 2G system ------------ 2G RAM would need 2M for vmemmap with struct page size being 64B. 1 PUD table for 2G memory (1G mapping) 1 PUD table and 1 PMD table for 2M vmemmap (2M mappings) With default PUD[PMD]_TABLE_SIZE(4K), (1+1+1)*4K=12K With new PAGE_SIZE(64K) table allocations, (1+1+1)*64K=192K Signed-off-by: Bharata B Rao <bharata@linux.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200709131925.922266-2-aneesh.kumar@linux.ibm.com
| * Merge branch 'fixes' into nextMichael Ellerman2020-07-182-8/+8
| |\ | | | | | | | | | | | | Merge our fixes branch, primarily to bring in the ebb selftests build fix and the pkey fix, which is a dependency for some future work.
| * | powerpc/numa: remove arch_update_cpu_topologyNathan Lynch2020-07-161-10/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since arch_update_cpu_topology() doesn't do anything on powerpc now, remove it and associated dead code. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200612051238.1007764-15-nathanl@linux.ibm.com
| * | powerpc/numa: remove prrn_is_enabled()Nathan Lynch2020-07-161-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | All users of this prrn_is_enabled() are gone; remove it. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200612051238.1007764-14-nathanl@linux.ibm.com
| * | powerpc/numa: remove start/stop_topology_update()Nathan Lynch2020-07-161-20/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | These APIs have become no-ops, so remove them and all call sites. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200612051238.1007764-12-nathanl@linux.ibm.com
| * | powerpc/numa: remove timed_topology_update()Nathan Lynch2020-07-161-9/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | timed_topology_update is a no-op now, so remove it and all call sites. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200612051238.1007764-11-nathanl@linux.ibm.com
| * | powerpc/numa: stub out numa_update_cpu_topology()Nathan Lynch2020-07-161-192/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previous changes have removed the code which sets bits in cpu_associativity_changes_mask and thus it is never modifed at runtime. From this we can reason that numa_update_cpu_topology() always returns 0 without doing anything. Remove the body of numa_update_cpu_topology() and remove all code which becomes unreachable as a result. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200612051238.1007764-10-nathanl@linux.ibm.com