Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-03 Thread Roland McGrath
> > config COMPAT_VDSO > > def_bool y > > prompt "Compat VDSO support" > > depends on X86_32 || IA32_EMULATION > > ---help--- > > Map the 32-bit VDSO to the predictable old-style address too. > > > > Say N here if you are running a sufficiently

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-03 Thread Roland McGrath
config COMPAT_VDSO def_bool y prompt Compat VDSO support depends on X86_32 || IA32_EMULATION ---help--- Map the 32-bit VDSO to the predictable old-style address too. Say N here if you are running a sufficiently recent glibc

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-02 Thread H. Peter Anvin
Sorry, I did not know/realize, and unfortunately "he" is the grammatical default in English, although the singular they is fortunately making a comeback. I stand corrected, through. Please acer my apologies. -hpa On February 2, 2014 3:20:25 AM PST, Stefani Seibold wrote: > >> >> >> >>

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-02 Thread Stefani Seibold
> >> > >> -#define VDSO_HIGH_BASE 0xe000U /* CONFIG_COMPAT_VDSO address > >> */ > >> +#define VDSO_HIGH_BASE 0xc000U /* CONFIG_COMPAT_VDSO address > >> */ > > > > This is odd. Can you explain it? > > > > He needs 3 pages instead of 1 after his changes. > Not every

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-02 Thread Stefani Seibold
-#define VDSO_HIGH_BASE 0xe000U /* CONFIG_COMPAT_VDSO address */ +#define VDSO_HIGH_BASE 0xc000U /* CONFIG_COMPAT_VDSO address */ This is odd. Can you explain it? He needs 3 pages instead of 1 after his changes. Not every kernel hackers a male.

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-02 Thread H. Peter Anvin
Sorry, I did not know/realize, and unfortunately he is the grammatical default in English, although the singular they is fortunately making a comeback. I stand corrected, through. Please acer my apologies. -hpa On February 2, 2014 3:20:25 AM PST, Stefani Seibold stef...@seibold.net wrote:

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread H. Peter Anvin
On 02/01/2014 04:41 PM, H. Peter Anvin wrote: >> >> Right. But there's some obscure ABI reason for CONFIG_COMPAT_VDSO, >> and if this breaks it, then it's no good. From extremely vague >> memory, there's some version of SuSE that breaks if the 32-bit vdso >> moves. I have no idea what the bug

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread H. Peter Anvin
Yes, that we can move, of course. On February 1, 2014 4:30:17 PM PST, Andy Lutomirski wrote: >On Sat, Feb 1, 2014 at 4:26 PM, H. Peter Anvin wrote: >> On 02/01/2014 03:59 PM, Andy Lutomirski wrote: >>> >>> If it is, indeed, okay to use non-fixed maps on 32-bit, it might >>> also be okay on

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread Andy Lutomirski
On Sat, Feb 1, 2014 at 4:26 PM, H. Peter Anvin wrote: > On 02/01/2014 03:59 PM, Andy Lutomirski wrote: >> >> If it is, indeed, okay to use non-fixed maps on 32-bit, it might >> also be okay on 64-bit. If so, it could be useful to implement that, >> which would remove a bit of a wart and allow

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread H. Peter Anvin
On 02/01/2014 03:59 PM, Andy Lutomirski wrote: > > If it is, indeed, okay to use non-fixed maps on 32-bit, it might > also be okay on 64-bit. If so, it could be useful to implement that, > which would remove a bit of a wart and allow PR_SET_TSC to work > usefully for 64-bit userspace. (This

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread Andy Lutomirski
On Sat, Feb 1, 2014 at 7:32 AM, wrote: > From: Stefani Seibold > > This patch add the time support for 32 bit a VDSO to a 32 bit kernel. > > For 32 bit programs running on a 32 bit kernel, the same mechanism is > used as for 64 bit programs running on a 64 bit kernel. > > Signed-off-by: Stefani

[PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread stefani
From: Stefani Seibold This patch add the time support for 32 bit a VDSO to a 32 bit kernel. For 32 bit programs running on a 32 bit kernel, the same mechanism is used as for 64 bit programs running on a 64 bit kernel. Signed-off-by: Stefani Seibold --- arch/x86/include/asm/elf.h|

[PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread stefani
From: Stefani Seibold stef...@seibold.net This patch add the time support for 32 bit a VDSO to a 32 bit kernel. For 32 bit programs running on a 32 bit kernel, the same mechanism is used as for 64 bit programs running on a 64 bit kernel. Signed-off-by: Stefani Seibold stef...@seibold.net ---

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread Andy Lutomirski
On Sat, Feb 1, 2014 at 7:32 AM, stef...@seibold.net wrote: From: Stefani Seibold stef...@seibold.net This patch add the time support for 32 bit a VDSO to a 32 bit kernel. For 32 bit programs running on a 32 bit kernel, the same mechanism is used as for 64 bit programs running on a 64 bit

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread H. Peter Anvin
On 02/01/2014 03:59 PM, Andy Lutomirski wrote: If it is, indeed, okay to use non-fixed maps on 32-bit, it might also be okay on 64-bit. If so, it could be useful to implement that, which would remove a bit of a wart and allow PR_SET_TSC to work usefully for 64-bit userspace. (This would

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread Andy Lutomirski
On Sat, Feb 1, 2014 at 4:26 PM, H. Peter Anvin h...@zytor.com wrote: On 02/01/2014 03:59 PM, Andy Lutomirski wrote: If it is, indeed, okay to use non-fixed maps on 32-bit, it might also be okay on 64-bit. If so, it could be useful to implement that, which would remove a bit of a wart and

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread H. Peter Anvin
Yes, that we can move, of course. On February 1, 2014 4:30:17 PM PST, Andy Lutomirski l...@amacapital.net wrote: On Sat, Feb 1, 2014 at 4:26 PM, H. Peter Anvin h...@zytor.com wrote: On 02/01/2014 03:59 PM, Andy Lutomirski wrote: If it is, indeed, okay to use non-fixed maps on 32-bit, it

Re: [PATCH 3/4] Add 32 bit VDSO time support for 32 bit kernel

2014-02-01 Thread H. Peter Anvin
On 02/01/2014 04:41 PM, H. Peter Anvin wrote: Right. But there's some obscure ABI reason for CONFIG_COMPAT_VDSO, and if this breaks it, then it's no good. From extremely vague memory, there's some version of SuSE that breaks if the 32-bit vdso moves. I have no idea what the bug is, but