On 25/06/2015 09:12, Geert Uytterhoeven wrote: > On Thu, Jun 25, 2015 at 6:08 AM, Linux Kernel Mailing List > <linux-kernel@xxxxxxxxxxxxxxx> wrote: >> Gitweb: http://git.kernel.org/linus/;a=commit;h=2ae416b142b625c58c9ccb039aa3ef48ad0e9bae >> Commit: 2ae416b142b625c58c9ccb039aa3ef48ad0e9bae >> Parent: e81f2d22370f8231cb7f13f454bcc8c0eb4e23f2 >> Refname: refs/heads/master >> Author: Laurent Dufour <ldufour@xxxxxxxxxxxxxxxxxx> >> AuthorDate: Wed Jun 24 16:56:16 2015 -0700 >> Committer: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> >> CommitDate: Wed Jun 24 17:49:41 2015 -0700 >> >> mm: new mm hook framework >> >> CRIU is recreating the process memory layout by remapping the checkpointee >> memory area on top of the current process (criu). This includes remapping >> the vDSO to the place it has at checkpoint time. >> >> However some architectures like powerpc are keeping a reference to the >> vDSO base address to build the signal return stack frame by calling the >> vDSO sigreturn service. So once the vDSO has been moved, this reference >> is no more valid and the signal frame built later are not usable. >> >> This patch serie is introducing a new mm hook framework, and a new >> arch_remap hook which is called when mremap is done and the mm lock still >> hold. The next patch is adding the vDSO remap and unmap tracking to the >> powerpc architecture. >> >> This patch (of 3): >> >> This patch introduces a new set of header file to manage mm hooks: >> - per architecture empty header file (arch/x/include/asm/mm-arch-hooks.h) >> - a generic header (include/linux/mm-arch-hooks.h) >> >> The architecture which need to overwrite a hook as to redefine it in its >> header file, while architecture which doesn't need have nothing to do. >> >> The default hooks are defined in the generic header and are used in the >> case the architecture is not defining it. >> >> In a next step, mm hooks defined in include/asm-generic/mm_hooks.h should >> be moved here. >> >> Signed-off-by: Laurent Dufour <ldufour@xxxxxxxxxxxxxxxxxx> >> Suggested-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> >> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> >> Cc: Hugh Dickins <hughd@xxxxxxxxxx> >> Cc: Rik van Riel <riel@xxxxxxxxxx> >> Cc: Mel Gorman <mgorman@xxxxxxx> >> Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx> >> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> >> Cc: Paul Mackerras <paulus@xxxxxxxxx> >> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> >> Cc: Ingo Molnar <mingo@xxxxxxxxxx> >> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> >> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> >> --- >> arch/alpha/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/arc/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/arm/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/arm64/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/avr32/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/blackfin/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/c6x/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/cris/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/frv/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/hexagon/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/ia64/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/m32r/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/m68k/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/metag/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/microblaze/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/mips/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/mn10300/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/nios2/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/openrisc/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/parisc/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/powerpc/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/s390/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/score/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/sh/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/sparc/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/tile/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/um/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/unicore32/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/x86/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> arch/xtensa/include/asm/mm-arch-hooks.h | 15 +++++++++++++++ >> include/linux/mm-arch-hooks.h | 16 ++++++++++++++++ > > Touching all arch/ directories without a CC to linux-arch? I apologizes, this thread initially was only involving arch/powerpc files, and following multiple advices it came to impact all arch. > >> 31 files changed, 466 insertions(+) >> >> diff --git a/arch/alpha/include/asm/mm-arch-hooks.h b/arch/alpha/include/asm/mm-arch-hooks.h >> new file mode 100644 >> index 0000000..b07fd86 >> --- /dev/null >> +++ b/arch/alpha/include/asm/mm-arch-hooks.h >> @@ -0,0 +1,15 @@ >> +/* >> + * Architecture specific mm hooks >> + * >> + * Copyright (C) 2015, IBM Corporation >> + * Author: Laurent Dufour <ldufour@xxxxxxxxxxxxxxxxxx> > > Cool, copyright on an empty header! > >> + * >> + * 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. >> + */ >> + >> +#ifndef _ASM_ALPHA_MM_ARCH_HOOKS_H >> +#define _ASM_ALPHA_MM_ARCH_HOOKS_H >> + >> +#endif /* _ASM_ALPHA_MM_ARCH_HOOKS_H */ > > [...] > > IMHO this screams for the generic version in include/asm-generic/, > and "generic-y += mm-arch-hooks.h" in arch/*/include/asm/Kbuild/. I do like your proposal which avoid creating too many *empty* files. Since Andrew suggested the way I did the current patch, I'd appreciate his feedback too. > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>