kernel.git/arch/arc/include/asm/page.h, branch linux-5.13.y

ARC: mm: PAE: use 40-bit physical page mask

2021-05-10T19:38:59Z

32-bit PAGE_MASK can not be used as a mask for physical addresses when PAE is enabled. PAGE_MASK_PHYS must be used for physical addresses instead of PAGE_MASK. Without this, init gets SIGSEGV if pte_modify was called: | potentially unexpected fatal signal 11. | Path: /bin/busybox | CPU: 0 PID: 1 Comm: init Not tainted 5.12.0-rc5-00003-g1e43c377a79f-dirty | Insn could not be fetched | @No matching VMA found | ECR: 0x00040000 EFA: 0x00000000 ERET: 0x00000000 | STAT: 0x80080082 [IE U ] BTA: 0x00000000 | SP: 0x5f9ffe44 FP: 0x00000000 BLK: 0xaf3d4 | LPS: 0x000d093e LPE: 0x000d0950 LPC: 0x00000000 | r00: 0x00000002 r01: 0x5f9fff14 r02: 0x5f9fff20 | ... | Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Signed-off-by: Vladimir Isaev Reported-by: kernel test robot Cc: Vineet Gupta Cc: stable@vger.kernel.org Signed-off-by: Vineet Gupta

arch/arc: add copy_user_page() to to fix build error on ARC

2021-01-05T20:59:40Z

fs/dax.c uses copy_user_page() but ARC does not provide that interface, resulting in a build error. Provide copy_user_page() in . ../fs/dax.c: In function 'copy_cow_page_dax': ../fs/dax.c:702:2: error: implicit declaration of function 'copy_user_page'; did you mean 'copy_to_user_page'? [-Werror=implicit-function-declaration] Reported-by: kernel test robot Signed-off-by: Randy Dunlap Cc: Vineet Gupta Cc: linux-snps-arc@lists.infradead.org Cc: Dan Williams #Acked-by: Vineet Gupta # v1 Cc: Andrew Morton Cc: Matthew Wilcox Cc: Jan Kara Cc: linux-fsdevel@vger.kernel.org Cc: linux-nvdimm@lists.01.org #Reviewed-by: Ira Weiny # v2 Signed-off-by: Vineet Gupta

arc: use FLATMEM with freeing of unused memory map instead of DISCONTIGMEM

2020-12-15T20:13:42Z

Currently ARC uses DISCONTIGMEM to cope with sparse physical memory address space on systems with 2 memory banks. While DISCONTIGMEM avoids wasting memory on unpopulated memory map, it adds both memory and CPU overhead relatively to FLATMEM. Moreover, DISCONTINGMEM is generally considered deprecated. The obvious replacement for DISCONTIGMEM would be SPARSEMEM, but it is also less efficient than FLATMEM in pfn_to_page() and page_to_pfn() conversions. Besides it requires tuning of SECTION_SIZE which is not trivial for possible ARC memory configuration. Since the memory map for both banks is always allocated from the "lowmem" bank, it is possible to use FLATMEM for two-bank configuration and simply free the unused hole in the memory map. All is required for that is to provide ARC-specific pfn_valid() that will take into account actual physical memory configuration and define HAVE_ARCH_PFN_VALID. The resulting kernel image configured with defconfig + HIGHMEM=y is smaller: $ size a/vmlinux b/vmlinux text data bss dec hex filename 4673503 1245456 279756 6198715 5e95bb a/vmlinux 4658706 1246864 279756 6185326 5e616e b/vmlinux $ ./scripts/bloat-o-meter a/vmlinux b/vmlinux add/remove: 28/30 grow/shrink: 42/399 up/down: 10986/-29025 (-18039) ... Total: Before=4709315, After = 4691276, chg -0.38% Booting nSIM with haps_ns.dts results in the following memory usage reports: a: Memory: 1559104K/1572864K available (3531K kernel code, 595K rwdata, 752K rodata, 136K init, 275K bss, 13760K reserved, 0K cma-reserved, 1048576K highmem) b: Memory: 1559112K/1572864K available (3519K kernel code, 594K rwdata, 752K rodata, 136K init, 280K bss, 13752K reserved, 0K cma-reserved, 1048576K highmem) Link: https://lkml.kernel.org/r/20201101170454.9567-11-rppt@kernel.org Signed-off-by: Mike Rapoport Cc: Alexey Dobriyan Cc: Catalin Marinas Cc: Geert Uytterhoeven Cc: Greg Ungerer Cc: John Paul Adrian Glaubitz Cc: Jonathan Corbet Cc: Matt Turner Cc: Meelis Roos Cc: Michael Schmitz Cc: Russell King Cc: Tony Luck Cc: Vineet Gupta Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS

2020-04-10T22:36:21Z

There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the existing VM_STACK_DEFAULT_FLAGS. While here, also define some more macros with standard VMA access flag combinations that are used frequently across many platforms. Apart from simplification, this reduces code duplication as well. Signed-off-by: Anshuman Khandual Signed-off-by: Andrew Morton Reviewed-by: Vlastimil Babka Acked-by: Geert Uytterhoeven Cc: Richard Henderson Cc: Vineet Gupta Cc: Russell King Cc: Catalin Marinas Cc: Mark Salter Cc: Guo Ren Cc: Yoshinori Sato Cc: Brian Cain Cc: Tony Luck Cc: Michal Simek Cc: Ralf Baechle Cc: Paul Burton Cc: Nick Hu Cc: Ley Foon Tan Cc: Jonas Bonn Cc: "James E.J. Bottomley" Cc: Michael Ellerman Cc: Paul Walmsley Cc: Heiko Carstens Cc: Rich Felker Cc: "David S. Miller" Cc: Guan Xuetao Cc: Thomas Gleixner Cc: Jeff Dike Cc: Chris Zankel Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55Z

Based on 2 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 version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

ARC: mm: allow mprotect to make stack mappings executable

2018-07-11T18:03:06Z

mprotect(EXEC) was failing for stack mappings as default vm flags was missing MAYEXEC. This was triggered by glibc test suite nptl/tst-execstack testcase What is surprising is that despite running LTP for years on, we didn't catch this issue as it lacks a directed test case. gcc dejagnu tests with nested functions also requiring exec stack work fine though because they rely on the GNU_STACK segment spit out by compiler and handled in kernel elf loader. This glibc case is different as the stack is non exec to begin with and a dlopen of shared lib with GNU_STACK segment triggers the exec stack proceedings using a mprotect(PROT_EXEC) which was broken. CC: stable@vger.kernel.org Signed-off-by: Vineet Gupta

ARC: mm: Decouple RAM base address from kernel link address

2017-09-01T18:26:27Z

[Needed for HSDK] Currently the first page of system (hence RAM base) is assumed to be @ CONFIG_LINUX_LINK_BASE, where kernel itself is linked. However is case of HSDK platform, for reasons explained in that patch, this is not true. kernel needs to be linked @ 0x9000_0000 while DDR is still wired at 0x8000_0000. To properly account for this 256M of RAM, we need to introduce a new option and base page frame accountiing off of it. Signed-off-by: Eugeniy Paltsev Signed-off-by: Vineet Gupta [vgupta: renamed CONFIG_KERNEL_RAM_BASE_ADDRESS => CONFIG_LINUX_RAM_BASE : simplified changelog]

ARC: pae: STRICT_MM_TYPECHECKS was broken

2016-05-13T03:46:09Z

Signed-off-by: Vineet Gupta

ARC: support HIGHMEM even without PAE40

2016-05-05T11:05:46Z

Initial HIGHMEM support on ARC was introduced for PAE40 where the low memory (0x8000_0000 based) and high memory (0x1_0000_0000) were physically contiguous. So CONFIG_FLATMEM sufficed (despite a peipheral hole in the middle, which wasted a bit of struct page memory, but things worked). However w/o PAE, highmem was not possible and we could only reach ~1.75GB of DDR. Now there is a use case to access ~4GB of DDR w/o PAE40 The idea is to have low memory at canonical 0x8000_0000 and highmem at 0 so enire 4GB address space is available for physical addressing This needs additional platform/interconnect mapping to convert the non contiguous physical addresses into linear bus adresses. From Linux point of view, non contiguous divide means FLATMEM no longer works and DISCONTIGMEM is needed to track the pfns in the 2 regions. This scheme would also work for PAE40, only better in that we don't waste struct page memory for the peripheral hole. The DT description will be something like memory { ... reg = <0x80000000 0x200000000 /* 512MB: lowmem */ 0x00000000 0x10000000>; /* 256MB: highmem */ } Signed-off-by: Noam Camus Signed-off-by: Vineet Gupta

ARC: Fix PAE40 boot failures due to PTE truncation

2016-05-05T11:05:45Z

So a benign looking cleanup which macro'ized PAGE_SHIFT shifts turned out to be bad (since it was done non-sensically across the board). It caused boot failures with PAE40 as forced cast to (unsigned long) from newly introduced virt_to_pfn() was causing truncatiion of the (long long) pte/paddr values. It is OK to use this in accessors dealing with kernel virtual address, pointers etc, but not for PTE values themelves. Fixes: cJ2ff5cf2735c ("ARC: mm: Use virt_to_pfn() for addr >> PAGE_SHIFT pattern) Signed-off-by: Vineet Gupta