Re: [PATCH v2 2/5] powerpc: Allow 4224 bytes of stack expansion for the signal frame

2020-07-27 Thread Michael Ellerman
Gabriel Paubert writes: > On Fri, Jul 24, 2020 at 07:25:25PM +1000, Michael Ellerman wrote: >> We have powerpc specific logic in our page fault handling to decide if >> an access to an unmapped address below the stack pointer should expand >> the stack VMA. >> >> The code was originally added in

Re: [PATCH v2 2/5] powerpc: Allow 4224 bytes of stack expansion for the signal frame

2020-07-27 Thread Daniel Axtens
Hi Michael, I have tested this with the test from the bug and it now seems to pass fine. On that basis: Tested-by: Daniel Axtens Thank you for coming up with a better solution than my gross hack! Kind regards, Daniel > We have powerpc specific logic in our page fault handling to decide if > a

Re: [PATCH v2 2/5] powerpc: Allow 4224 bytes of stack expansion for the signal frame

2020-07-27 Thread Gabriel Paubert
On Fri, Jul 24, 2020 at 07:25:25PM +1000, Michael Ellerman wrote: > We have powerpc specific logic in our page fault handling to decide if > an access to an unmapped address below the stack pointer should expand > the stack VMA. > > The code was originally added in 2004 "ported from 2.4". The roug

[PATCH v2 2/5] powerpc: Allow 4224 bytes of stack expansion for the signal frame

2020-07-24 Thread Michael Ellerman
We have powerpc specific logic in our page fault handling to decide if an access to an unmapped address below the stack pointer should expand the stack VMA. The code was originally added in 2004 "ported from 2.4". The rough logic is that the stack is allowed to grow to 1MB with no extra checking.