forked from Minki/linux
mainlining shenanigans
2103cf9c3f
Patch series "mm/hugetlb: Early cow on fork, and a few cleanups", v5. As reported by Gal [1], we still miss the code clip to handle early cow for hugetlb case, which is true. Again, it still feels odd to fork() after using a few huge pages, especially if they're privately mapped to me.. However I do agree with Gal and Jason in that we should still have that since that'll complete the early cow on fork effort at least, and it'll still fix issues where buffers are not well under control and not easy to apply MADV_DONTFORK. The first two patches (1-2) are some cleanups I noticed when reading into the hugetlb reserve map code. I think it's good to have but they're not necessary for fixing the fork issue. The last two patches (3-4) are the real fix. I tested this with a fork() after some vfio-pci assignment, so I'm pretty sure the page copy path could trigger well (page will be accounted right after the fork()), but I didn't do data check since the card I assigned is some random nic. https://github.com/xzpeter/linux/tree/fork-cow-pin-huge [1] https://lore.kernel.org/lkml/27564187-4a08-f187-5a84-3df50009f6ca@amazon.com/ Introduce hugetlb_resv_map_add() helper to add a new file_region rather than duplication the similar code twice in add_reservation_in_range(). Link: https://lkml.kernel.org/r/20210217233547.93892-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20210217233547.93892-2-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Cc: Gal Pressman <galpress@amazon.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Wei Zhang <wzam@amazon.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jann Horn <jannh@google.com> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Kirill Shutemov <kirill@shutemov.name> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Roland Scheidegger <sroland@vmware.com> Cc: VMware Graphics <linux-graphics-maintainer@vmware.com> 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 | ||
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. 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.