user/sven/linux.git/Documentation/core-api, branch v5.4.43

Merge tag 'modules-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

2019-10-11T17:19:24Z

Pull module fixes from Jessica Yu: "Code cleanups and kbuild/namespace related fixups from Masahiro. Most importantly, it fixes a namespace-related modpost issue for external module builds - Fix broken external module builds due to a modpost bug in read_dump(), where the namespace was not being strdup'd and sym->namespace would be set to bogus data. - Various namespace-related kbuild fixes and cleanups thanks to Masahiro Yamada" * tag 'modules-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: doc: move namespaces.rst from kbuild/ to core-api/ nsdeps: make generated patches independent of locale nsdeps: fix hashbang of scripts/nsdeps kbuild: fix build error of 'make nsdeps' in clean tree module: rename __kstrtab_ns_* to __kstrtabns_* to avoid symbol conflict modpost: fix broken sym->namespace for external module builds module: swap the order of symbol.namespace scripts: add_namespace: Fix coccicheck failed

doc: move namespaces.rst from kbuild/ to core-api/

2019-10-08T15:40:01Z

We discussed a better location for this file, and agreed that core-api/ is a good fit. Rename it to symbol-namespaces.rst for disambiguation, and also add it to index.rst and MAINTAINERS. Signed-off-by: Masahiro Yamada Acked-by: Matthias Maennich Signed-off-by: Jessica Yu

mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)

2019-10-07T22:47:20Z

In most configurations, kmalloc() happens to return naturally aligned (i.e. aligned to the block size itself) blocks for power of two sizes. That means some kmalloc() users might unknowingly rely on that alignment, until stuff breaks when the kernel is built with e.g. CONFIG_SLUB_DEBUG or CONFIG_SLOB, and blocks stop being aligned. Then developers have to devise workaround such as own kmem caches with specified alignment [1], which is not always practical, as recently evidenced in [2]. The topic has been discussed at LSF/MM 2019 [3]. Adding a 'kmalloc_aligned()' variant would not help with code unknowingly relying on the implicit alignment. For slab implementations it would either require creating more kmalloc caches, or allocate a larger size and only give back part of it. That would be wasteful, especially with a generic alignment parameter (in contrast with a fixed alignment to size). Ideally we should provide to mm users what they need without difficult workarounds or own reimplementations, so let's make the kmalloc() alignment to size explicitly guaranteed for power-of-two sizes under all configurations. What this means for the three available allocators? * SLAB object layout happens to be mostly unchanged by the patch. The implicitly provided alignment could be compromised with CONFIG_DEBUG_SLAB due to redzoning, however SLAB disables redzoning for caches with alignment larger than unsigned long long. Practically on at least x86 this includes kmalloc caches as they use cache line alignment, which is larger than that. Still, this patch ensures alignment on all arches and cache sizes. * SLUB layout is also unchanged unless redzoning is enabled through CONFIG_SLUB_DEBUG and boot parameter for the particular kmalloc cache. With this patch, explicit alignment is guaranteed with redzoning as well. This will result in more memory being wasted, but that should be acceptable in a debugging scenario. * SLOB has no implicit alignment so this patch adds it explicitly for kmalloc(). The potential downside is increased fragmentation. While pathological allocation scenarios are certainly possible, in my testing, after booting a x86_64 kernel+userspace with virtme, around 16MB memory was consumed by slab pages both before and after the patch, with difference in the noise. [1] https://lore.kernel.org/linux-btrfs/c3157c8e8e0e7588312b40c853f65c02fe6c957a.1566399731.git.christophe.leroy@c-s.fr/ [2] https://lore.kernel.org/linux-fsdevel/20190225040904.5557-1-ming.lei@redhat.com/ [3] https://lwn.net/Articles/787740/ [akpm@linux-foundation.org: documentation fixlet, per Matthew] Link: http://lkml.kernel.org/r/20190826111627.7505-3-vbabka@suse.cz Signed-off-by: Vlastimil Babka Reviewed-by: Matthew Wilcox (Oracle) Acked-by: Michal Hocko Acked-by: Kirill A. Shutemov Acked-by: Christoph Hellwig Cc: David Sterba Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Ming Lei Cc: Dave Chinner Cc: "Darrick J . Wong" Cc: Christoph Hellwig Cc: James Bottomley Cc: Vlastimil Babka Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kernel-doc: core-api: include string.h into core-api

2019-09-26T00:51:39Z

core-api should show all the various string functions including the newly added stracpy and stracpy_pad. Miscellanea: o Update the Returns: value for strscpy o fix a defect with %NUL) [joe@perches.com: correct return of -E2BIG descriptions] Link: http://lkml.kernel.org/r/29f998b4c1a9d69fbeae70500ba0daa4b340c546.1563889130.git.joe@perches.com Link: http://lkml.kernel.org/r/224a6ebf39955f4107c0c376d66155d970e46733.1563841972.git.joe@perches.com Signed-off-by: Joe Perches Reviewed-by: Kees Cook Cc: Jonathan Corbet Cc: Stephen Kitt Cc: Nitin Gote Cc: Rasmus Villemoes Cc: Jann Horn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

docs: printk-formats: Stop encouraging use of unnecessary %h[xudi] and %hh[xudi]

2019-09-14T07:57:43Z

Standard integer promotion is already done and %hx and %hhx is useless so do not encourage the use of %hh[xudi] or %h[xudi]. As Linus said in: https://lore.kernel.org/lkml/CAHk-=wgoxnmsj8GEVFJSvTwdnWm8wVJthefNk2n6+4TC=20e0Q@mail.gmail.com/ It's a pointless warning, making for more complex code, and making people remember esoteric printf format details that have no reason for existing. The "h" and "hh" things should never be used. The only reason for them being used if if you have an "int", but you want to print it out as a "char" (and honestly, that is a really bad reason, you'd be better off just using a proper cast to make the code more obvious). So if what you have a "char" (or unsigned char) you should always just print it out as an "int", knowing that the compiler already did the proper type conversion. Signed-off-by: Joe Perches Reviewed-by: Louis Taylor Signed-off-by: Jonathan Corbet

docs: index.rst: don't use genindex for pdf output

2019-07-31T19:31:16Z

The genindex logic is meant to be used only for html output, as pdf build has its own way to generate indexes. Signed-off-by: Mauro Carvalho Chehab Acked-by: Vinod Koul # dmaengine and soundwire Signed-off-by: Jonathan Corbet

docs: packing: move it to core-api book and adjust markups

2019-07-31T19:30:01Z

The packing.txt file was misplaced, as docs should be part of a documentation book, and not at the root dir. So, move it to the core-api directory and add to its index. Also, ensure that the file will be properly parsed and the bitmap ascii artwork will use a monotonic font. Fixes: 554aae35007e ("lib: Add support for generic packing operations") Signed-off-by: Mauro Carvalho Chehab Reviewed-by: Vladimir Oltean Tested-by: Vladimir Oltean Reviewed-by: Mike Rapoport Signed-off-by: Jonathan Corbet

docs: remove extra conf.py files

2019-07-17T09:57:52Z

Now that the latex_documents are handled automatically, we can remove those extra conf.py files. Signed-off-by: Mauro Carvalho Chehab

docs: admin-guide: move sysctl directory to it

2019-07-15T14:03:01Z

The stuff under sysctl describes /sys interface from userspace point of view. So, add it to the admin-guide and remove the :orphan: from its index file. Signed-off-by: Mauro Carvalho Chehab

docs: move gcc_plugins.txt to core-api and rename to .rst

2019-07-15T12:20:27Z

The gcc_plugins.txt file is already a ReST file. Move it to the core-api book while renaming it. Signed-off-by: Mauro Carvalho Chehab Acked-by: Kees Cook