Re: [PATCH 02/33] mm: overload get_user_pages() functions

From	Dave Hansen <dave@sr71.net>
Newsgroups	linux.kernel
Subject	Re: [PATCH 02/33] mm: overload get_user_pages() functions
Date	2016-02-17 19:20 +0100
Message-ID	<r3eRH-1IR-1@gated-at.bofh.it> (permalink)
References	<r1t8t-3TO-3@gated-at.bofh.it> <r1tib-3WT-13@gated-at.bofh.it> <r2JkR-5nT-1@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

On 02/16/2016 12:36 AM, Ingo Molnar wrote:
>> > From: Dave Hansen <dave.hansen@linux.intel.com>
>> > 
>> > The concept here was a suggestion from Ingo.  The implementation
>> > horrors are all mine.
>> > 
>> > This allows get_user_pages(), get_user_pages_unlocked(), and
>> > get_user_pages_locked() to be called with or without the
>> > leading tsk/mm arguments.  We will give a compile-time warning
>> > about the old style being __deprecated and we will also
>> > WARN_ON() if the non-remote version is used for a remote-style
>> > access.
> So at minimum this should be WARN_ON_ONCE(), to make it easier to recover some 
> meaningful kernel log from such incidents.

I went to go fix this in the code but realized that I coded it up as
WARN_ONCE().  The description was just imprecise.  So I won't be sending
a code fix for this.

Thread

[PATCH 00/33] x86: Memory Protection Keys (v10) Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
  [PATCH 18/33] x86, mm: simplify get_user_pages() PTE bit handling Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
    [tip:mm/pkeys] x86/mm/gup: Simplify get_user_pages()   PTE bit handling tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:30 +0100
  [PATCH 23/33] x86, pkeys: dump PKRU with other kernel registers Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
    [tip:mm/pkeys] x86/mm/pkeys:   Dump PKRU with other kernel registers tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:30 +0100
  [PATCH 30/33] x86, fpu: allow setting of XSAVE state Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
    [tip:mm/pkeys] x86/fpu: Allow setting of XSAVE state tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:30 +0100
  [PATCH 03/33] mm, gup: switch callers of get_user_pages() to not pass tsk/mm Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
    [tip:mm/pkeys] mm/gup: Switch all callers of get_user_pages()   to not pass tsk/mm tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:20 +0100
  [PATCH 19/33] x86, pkeys: check VMAs and PTEs for protection keys Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
    [tip:mm/pkeys] mm/gup, x86/mm/pkeys:   Check VMAs and PTEs for protection keys tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:30 +0100
  [PATCH 26/33] x86, pkeys: actually enable Memory Protection Keys in CPU Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
    [tip:mm/pkeys] x86/mm/pkeys:   Actually enable Memory Protection Keys in the CPU tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:30 +0100
  [PATCH 07/33] x86, pkeys: define new CR4 bit Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
    [tip:mm/pkeys] x86/cpu, x86/mm/pkeys: Define new CR4 bit tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:20 +0100
  [PATCH 13/33] x86, pkeys: pass VMA down in to fault signal generation code Dave Hansen <dave@sr71.net> - 2016-02-12 22:10 +0100
    [tip:mm/pkeys] x86/mm/pkeys:   Pass VMA down in to fault signal generation code tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:30 +0100
  [PATCH 11/33] x86, pkeys: store protection in high VMA flags Dave Hansen <dave@sr71.net> - 2016-02-12 22:20 +0100
    [tip:mm/pkeys] mm/core, x86/mm/pkeys:   Store protection bits in high VMA flags tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:30 +0100
  [PATCH 10/33] x86, pkeys: new page fault error code bit: PF_PK Dave Hansen <dave@sr71.net> - 2016-02-12 22:20 +0100
    [tip:mm/pkeys] x86/mm/pkeys: Add new 'PF_PK'   page fault error code bit tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:20 +0100
  [PATCH 09/33] x86, pkeys: PTE bits for storing protection key Dave Hansen <dave@sr71.net> - 2016-02-12 22:20 +0100
    [tip:mm/pkeys] x86/mm/pkeys:   Add PTE bits for storing protection key tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:20 +0100
  [PATCH 06/33] x86, pkeys: cpuid bit definition Dave Hansen <dave@sr71.net> - 2016-02-12 22:20 +0100
    [tip:mm/pkeys] x86/cpufeature, x86/mm/pkeys:   Add protection keys related CPUID definitions tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:20 +0100
  [PATCH 02/33] mm: overload get_user_pages() functions Dave Hansen <dave@sr71.net> - 2016-02-12 22:20 +0100
    Re: [PATCH 02/33] mm: overload get_user_pages() functions Ingo Molnar <mingo@kernel.org> - 2016-02-16 09:40 +0100
      Re: [PATCH 02/33] mm: overload get_user_pages() functions Dave Hansen <dave@sr71.net> - 2016-02-17 19:20 +0100
    [tip:mm/pkeys] mm/gup: Overload get_user_pages() functions tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:20 +0100
  [PATCH 01/33] mm: introduce get_user_pages_remote() Dave Hansen <dave@sr71.net> - 2016-02-12 22:20 +0100
    Re: [PATCH 01/33] mm: introduce get_user_pages_remote() Balbir Singh <bsingharora@gmail.com> - 2016-02-15 07:10 +0100
      Re: [PATCH 01/33] mm: introduce get_user_pages_remote() Dave Hansen <dave@sr71.net> - 2016-02-15 17:30 +0100
    Re: [PATCH 01/33] mm: introduce get_user_pages_remote() Srikar Dronamraju <srikar@linux.vnet.ibm.com> - 2016-02-15 07:20 +0100
    [tip:x86/pkeys] mm/gup: Introduce get_user_pages_remote() tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-16 13:20 +0100
      Re: [tip:x86/pkeys] mm/gup: Introduce get_user_pages_remote() Konstantin Khlebnikov <koct9i@gmail.com> - 2016-02-20 07:30 +0100
  [PATCH 05/33] x86, pkeys: Add Kconfig option Dave Hansen <dave@sr71.net> - 2016-02-12 22:20 +0100
    [tip:mm/pkeys] x86/mm/pkeys: Add Kconfig option tip-bot for Dave Hansen <tipbot@zytor.com> - 2016-02-18 21:20 +0100
      [PATCH] x86/mm/pkeys: Do not enable them by default Borislav Petkov <bp@alien8.de> - 2016-02-19 12:30 +0100
        Re: [PATCH] x86/mm/pkeys: Do not enable them by default Dave Hansen <dave@sr71.net> - 2016-02-19 18:20 +0100
          Re: [PATCH] x86/mm/pkeys: Do not enable them by default Borislav Petkov <bp@alien8.de> - 2016-02-19 18:30 +0100
            Re: [PATCH] x86/mm/pkeys: Do not enable them by default Dave Hansen <dave@sr71.net> - 2016-02-19 18:50 +0100
              Re: [PATCH] x86/mm/pkeys: Do not enable them by default Borislav Petkov <bp@alien8.de> - 2016-02-19 19:40 +0100
  Re: [PATCH 00/33] x86: Memory Protection Keys (v10) Ingo Molnar <mingo@kernel.org> - 2016-02-16 10:30 +0100

csiph-web