mainlining shenanigans
Mike Rapoport is converting architectures from bootmem to nobootmem allocator. While doing so for m68k Geert has noticed that he gets a scary looking warning: WARNING: CPU: 0 PID: 0 at mm/memblock.c:230 memblock_find_in_range_node+0x11c/0x1be memblock: bottom-up allocation failed, memory hotunplug may be affected Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 4.18.0-rc3-atari-01343-gf2fb5f2e09a97a3c-dirty #7 Call Trace: __warn+0xa8/0xc2 kernel_pg_dir+0x0/0x1000 netdev_lower_get_next+0x2/0x22 warn_slowpath_fmt+0x2e/0x36 memblock_find_in_range_node+0x11c/0x1be memblock_find_in_range_node+0x11c/0x1be memblock_find_in_range_node+0x0/0x1be vprintk_func+0x66/0x6e memblock_virt_alloc_internal+0xd0/0x156 netdev_lower_get_next+0x2/0x22 netdev_lower_get_next+0x2/0x22 kernel_pg_dir+0x0/0x1000 memblock_virt_alloc_try_nid_nopanic+0x58/0x7a netdev_lower_get_next+0x2/0x22 kernel_pg_dir+0x0/0x1000 kernel_pg_dir+0x0/0x1000 EXPTBL+0x234/0x400 EXPTBL+0x234/0x400 alloc_node_mem_map+0x4a/0x66 netdev_lower_get_next+0x2/0x22 free_area_init_node+0xe2/0x29e EXPTBL+0x234/0x400 paging_init+0x430/0x462 kernel_pg_dir+0x0/0x1000 printk+0x0/0x1a EXPTBL+0x234/0x400 setup_arch+0x1b8/0x22c start_kernel+0x4a/0x40a _sinittext+0x344/0x9e8 The warning is basically saying that a top-down allocation can break memory hotremove because memblock allocation is not movable. But m68k doesn't even support MEMORY_HOTREMOVE so there is no point to warn about it. Make the warning conditional only to configurations that care. Link: http://lkml.kernel.org/r/20180706061750.GH32658@dhcp22.suse.cz Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Sam Creasey <sammy@sammy.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.