user/sven/linux.git/include/linux/vmalloc.h, branch v5.15.87

mm: vmalloc: introduce array allocation functions

2022-07-12T14:35:01Z

[ Upstream commit a8749a35c39903120ec421ef2525acc8e0daa55c ] Linux has dozens of occurrences of vmalloc(array_size()) and vzalloc(array_size()). Allow to simplify the code by providing vmalloc_array and vcalloc, as well as the underscored variants that let the caller specify the GFP flags. Acked-by: Michal Hocko Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin

mm: defer kmemleak object creation of module_alloc()

2022-03-08T18:12:38Z

[ Upstream commit 60115fa54ad7b913b7cb5844e6b7ffeb842d55f2 ] Yongqiang reports a kmemleak panic when module insmod/rmmod with KASAN enabled(without KASAN_VMALLOC) on x86[1]. When the module area allocates memory, it's kmemleak_object is created successfully, but the KASAN shadow memory of module allocation is not ready, so when kmemleak scan the module's pointer, it will panic due to no shadow memory with KASAN check. module_alloc __vmalloc_node_range kmemleak_vmalloc kmemleak_scan update_checksum kasan_module_alloc kmemleak_ignore Note, there is no problem if KASAN_VMALLOC enabled, the modules area entire shadow memory is preallocated. Thus, the bug only exits on ARCH which supports dynamic allocation of module area per module load, for now, only x86/arm64/s390 are involved. Add a VM_DEFER_KMEMLEAK flags, defer vmalloc'ed object register of kmemleak in module_alloc() to fix this issue. [1] https://lore.kernel.org/all/6d41e2b9-4692-5ec4-b1cd-cbe29ae89739@huawei.com/ [wangkefeng.wang@huawei.com: fix build] Link: https://lkml.kernel.org/r/20211125080307.27225-1-wangkefeng.wang@huawei.com [akpm@linux-foundation.org: simplify ifdefs, per Andrey] Link: https://lkml.kernel.org/r/CA+fCnZcnwJHUQq34VuRxpdoY6_XbJCDJ-jopksS5Eia4PijPzw@mail.gmail.com Link: https://lkml.kernel.org/r/20211124142034.192078-1-wangkefeng.wang@huawei.com Fixes: 793213a82de4 ("s390/kasan: dynamic shadow mem allocation for modules") Fixes: 39d114ddc682 ("arm64: add KASAN support") Fixes: bebf56a1b176 ("kasan: enable instrumentation of global variables") Signed-off-by: Kefeng Wang Reported-by: Yongqiang Liu Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Catalin Marinas Cc: Will Deacon Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: Alexander Gordeev Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: Alexander Potapenko Cc: Kefeng Wang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

mm: move ioremap_page_range to vmalloc.c

2021-09-08T18:50:24Z

Patch series "small ioremap cleanups". The first patch moves a little code around the vmalloc/ioremap boundary following a bigger move by Nick earlier. The second enforces non-executable mapping on ioremap just like we do for vmap. No driver currently uses executable mappings anyway, as they should. This patch (of 2): This keeps it together with the implementation, and to remove the vmap_range wrapper. Link: https://lkml.kernel.org/r/20210824091259.1324527-1-hch@lst.de Link: https://lkml.kernel.org/r/20210824091259.1324527-2-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Nicholas Piggin Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: fix spelling mistakes in header files

2021-07-08T18:48:21Z

Fix some spelling mistakes in comments: successfull ==> successful potentialy ==> potentially alloced ==> allocated indicies ==> indices wont ==> won't resposible ==> responsible dirtyness ==> dirtiness droppped ==> dropped alread ==> already occured ==> occurred interupts ==> interrupts extention ==> extension slighly ==> slightly Dont't ==> Don't Link: https://lkml.kernel.org/r/20210531034849.9549-2-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei Cc: Jerome Glisse Cc: Mike Kravetz Cc: Dennis Zhou Cc: Tejun Heo Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/vmalloc: enable mapping of huge pages at pte level in vmalloc

2021-07-01T03:47:26Z

On some architectures like powerpc, there are huge pages that are mapped at pte level. Enable it in vmalloc. For that, architectures can provide arch_vmap_pte_supported_shift() that returns the shift for pages to map at pte level. Link: https://lkml.kernel.org/r/2c717e3b1fba1894d890feb7669f83025bfa314d.1620795204.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Michael Ellerman Cc: Mike Kravetz Cc: Mike Rapoport Cc: Nicholas Piggin Cc: Paul Mackerras Cc: Uladzislau Rezki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/vmalloc: enable mapping of huge pages at pte level in vmap

2021-07-01T03:47:26Z

On some architectures like powerpc, there are huge pages that are mapped at pte level. Enable it in vmap. For that, architectures can provide arch_vmap_pte_range_map_size() that returns the size of pages to map at pte level. Link: https://lkml.kernel.org/r/fb3ccc73377832ac6708181ec419128a2f98ce36.1620795204.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy Cc: Benjamin Herrenschmidt Cc: Michael Ellerman Cc: Mike Kravetz Cc: Mike Rapoport Cc: Nicholas Piggin Cc: Paul Mackerras Cc: Uladzislau Rezki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/vmalloc: add vmalloc_no_huge

2021-06-25T02:40:53Z

Patch series "mm: add vmalloc_no_huge and use it", v4. Add vmalloc_no_huge() and export it, so modules can allocate memory with small pages. Use the newly added vmalloc_no_huge() in KVM on s390 to get around a hardware limitation. This patch (of 2): Commit 121e6f3258fe3 ("mm/vmalloc: hugepage vmalloc mappings") added support for hugepage vmalloc mappings, it also added the flag VM_NO_HUGE_VMAP for __vmalloc_node_range to request the allocation to be performed with 0-order non-huge pages. This flag is not accessible when calling vmalloc, the only option is to call directly __vmalloc_node_range, which is not exported. This means that a module can't vmalloc memory with small pages. Case in point: KVM on s390x needs to vmalloc a large area, and it needs to be mapped with non-huge pages, because of a hardware limitation. This patch adds the function vmalloc_no_huge, which works like vmalloc, but it is guaranteed to always back the mapping using small pages. This new function is exported, therefore it is usable by modules. [akpm@linux-foundation.org: whitespace fixes, per Christoph] Link: https://lkml.kernel.org/r/20210614132357.10202-1-imbrenda@linux.ibm.com Link: https://lkml.kernel.org/r/20210614132357.10202-2-imbrenda@linux.ibm.com Fixes: 121e6f3258fe3 ("mm/vmalloc: hugepage vmalloc mappings") Signed-off-by: Claudio Imbrenda Reviewed-by: Uladzislau Rezki (Sony) Acked-by: Nicholas Piggin Reviewed-by: David Hildenbrand Acked-by: David Rientjes Cc: Uladzislau Rezki (Sony) Cc: Catalin Marinas Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Christoph Hellwig Cc: Cornelia Huck Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: fix typos in comments

2021-05-07T07:26:35Z

Fix ~94 single-word typos in locking code comments, plus a few very obvious grammar mistakes. Link: https://lkml.kernel.org/r/20210322212624.GA1963421@gmail.com Link: https://lore.kernel.org/r/20210322205203.GB1959563@gmail.com Signed-off-by: Ingo Molnar Reviewed-by: Matthew Wilcox (Oracle) Reviewed-by: Randy Dunlap Cc: Bhaskar Chowdhury Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/vmalloc: remove vwrite()

2021-05-07T07:26:34Z

The last user (/dev/kmem) is gone. Let's drop it. Link: https://lkml.kernel.org/r/20210324102351.6932-4-david@redhat.com Signed-off-by: David Hildenbrand Acked-by: Michal Hocko Cc: Linus Torvalds Cc: Greg Kroah-Hartman Cc: Hillf Danton Cc: Matthew Wilcox Cc: Oleksiy Avramchenko Cc: Steven Rostedt Cc: Minchan Kim Cc: huang ying Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drivers/char: remove /dev/kmem for good

2021-05-07T07:26:34Z

Patch series "drivers/char: remove /dev/kmem for good". Exploring /dev/kmem and /dev/mem in the context of memory hot(un)plug and memory ballooning, I started questioning the existence of /dev/kmem. Comparing it with the /proc/kcore implementation, it does not seem to be able to deal with things like a) Pages unmapped from the direct mapping (e.g., to be used by secretmem) -> kern_addr_valid(). virt_addr_valid() is not sufficient. b) Special cases like gart aperture memory that is not to be touched -> mem_pfn_is_ram() Unless I am missing something, it's at least broken in some cases and might fault/crash the machine. Looks like its existence has been questioned before in 2005 and 2010 [1], after ~11 additional years, it might make sense to revive the discussion. CONFIG_DEVKMEM is only enabled in a single defconfig (on purpose or by mistake?). All distributions disable it: in Ubuntu it has been disabled for more than 10 years, in Debian since 2.6.31, in Fedora at least starting with FC3, in RHEL starting with RHEL4, in SUSE starting from 15sp2, and OpenSUSE has it disabled as well. 1) /dev/kmem was popular for rootkits [2] before it got disabled basically everywhere. Ubuntu documents [3] "There is no modern user of /dev/kmem any more beyond attackers using it to load kernel rootkits.". RHEL documents in a BZ [5] "it served no practical purpose other than to serve as a potential security problem or to enable binary module drivers to access structures/functions they shouldn't be touching" 2) /proc/kcore is a decent interface to have a controlled way to read kernel memory for debugging puposes. (will need some extensions to deal with memory offlining/unplug, memory ballooning, and poisoned pages, though) 3) It might be useful for corner case debugging [1]. KDB/KGDB might be a better fit, especially, to write random memory; harder to shoot yourself into the foot. 4) "Kernel Memory Editor" [4] hasn't seen any updates since 2000 and seems to be incompatible with 64bit [1]. For educational purposes, /proc/kcore might be used to monitor value updates -- or older kernels can be used. 5) It's broken on arm64, and therefore, completely disabled there. Looks like it's essentially unused and has been replaced by better suited interfaces for individual tasks (/proc/kcore, KDB/KGDB). Let's just remove it. [1] https://lwn.net/Articles/147901/ [2] https://www.linuxjournal.com/article/10505 [3] https://wiki.ubuntu.com/Security/Features#A.2Fdev.2Fkmem_disabled [4] https://sourceforge.net/projects/kme/ [5] https://bugzilla.redhat.com/show_bug.cgi?id=154796 Link: https://lkml.kernel.org/r/20210324102351.6932-1-david@redhat.com Link: https://lkml.kernel.org/r/20210324102351.6932-2-david@redhat.com Signed-off-by: David Hildenbrand Acked-by: Michal Hocko Acked-by: Kees Cook Cc: Linus Torvalds Cc: Greg Kroah-Hartman Cc: "Alexander A. Klimov" Cc: Alexander Viro Cc: Alexandre Belloni Cc: Andrew Lunn Cc: Andrey Zhizhikin Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Brian Cain Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Chris Zankel Cc: Corentin Labbe Cc: "David S. Miller" Cc: "Eric W. Biederman" Cc: Geert Uytterhoeven Cc: Gerald Schaefer Cc: Greentime Hu Cc: Gregory Clement Cc: Heiko Carstens Cc: Helge Deller Cc: Hillf Danton Cc: huang ying Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: "James E.J. Bottomley" Cc: James Troup Cc: Jiaxun Yang Cc: Jonas Bonn Cc: Jonathan Corbet Cc: Kairui Song Cc: Krzysztof Kozlowski Cc: Kuninori Morimoto Cc: Liviu Dudau Cc: Lorenzo Pieralisi Cc: Luc Van Oostenryck Cc: Luis Chamberlain Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Mike Rapoport Cc: Mikulas Patocka Cc: Minchan Kim Cc: Niklas Schnelle Cc: Oleksiy Avramchenko Cc: openrisc@lists.librecores.org Cc: Palmer Dabbelt Cc: Paul Mackerras Cc: "Pavel Machek (CIP)" Cc: Pavel Machek Cc: "Peter Zijlstra (Intel)" Cc: Pierre Morel Cc: Randy Dunlap Cc: Richard Henderson Cc: Rich Felker Cc: Robert Richter Cc: Rob Herring Cc: Russell King Cc: Sam Ravnborg Cc: Sebastian Andrzej Siewior Cc: Sebastian Hesselbarth Cc: sparclinux@vger.kernel.org Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Steven Rostedt Cc: Sudeep Holla Cc: Theodore Dubois Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Viresh Kumar Cc: William Cohen Cc: Xiaoming Ni Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds