Re: Simplfying copy_siginfo_to_user

2017-07-31 Thread Eric W. Biederman
Al Viro writes: 2> On Mon, Jul 24, 2017 at 10:43:34AM -0700, Linus Torvalds wrote: >> On Sat, Jul 22, 2017 at 1:25 PM, Eric W. Biederman >> wrote: >> > I played with some clever changes such as limiting the copy to 48 bytes, >> > disabling the memset and the like but I could not get a strong eno

Re: Simplfying copy_siginfo_to_user

2017-07-24 Thread Al Viro
On Mon, Jul 24, 2017 at 10:43:34AM -0700, Linus Torvalds wrote: > On Sat, Jul 22, 2017 at 1:25 PM, Eric W. Biederman > wrote: > > I played with some clever changes such as limiting the copy to 48 bytes, > > disabling the memset and the like but I could not get a strong enough > > signal to say tha

Re: Simplfying copy_siginfo_to_user

2017-07-24 Thread Eric W. Biederman
Linus Torvalds writes: > On Sat, Jul 22, 2017 at 1:25 PM, Eric W. Biederman > wrote: >> I played with some clever changes such as limiting the copy to 48 bytes, >> disabling the memset and the like but I could not get a strong enough >> signal to say that any one change removed the extra or a cl

Re: Simplfying copy_siginfo_to_user

2017-07-24 Thread Linus Torvalds
On Sat, Jul 22, 2017 at 1:25 PM, Eric W. Biederman wrote: > I played with some clever changes such as limiting the copy to 48 bytes, > disabling the memset and the like but I could not get a strong enough > signal to say that any one change removed the extra or a clear part of > it 20ns. What CPU

Simplfying copy_siginfo_to_user

2017-07-22 Thread Eric W. Biederman
ebied...@xmission.com (Eric W. Biederman) writes: > Linus Torvalds writes: > >> On Tue, Jul 18, 2017 at 7:06 AM, Eric W. Biederman >> wrote: >>> struct siginfo is a union and the kernel since 2.4 has been hiding a union >>> tag in the high 16bits of si_code using the values: >>> __SI_KILL >>> __