Re: [patch 43/60] x86/fixmap: Add debugstore entries to cpu_entry_area

2017-12-07 Thread Borislav Petkov
On Mon, Dec 04, 2017 at 03:07:49PM +0100, Thomas Gleixner wrote: > From: Thomas Gleixner > > The intel PEBS/BTS debug store is a design trainwreck as is expects virtual > addresses which must be visible in any execution context. Sure, what can possibly go wrong?! :-\ > So

Re: [patch 43/60] x86/fixmap: Add debugstore entries to cpu_entry_area

2017-12-07 Thread Borislav Petkov
On Mon, Dec 04, 2017 at 03:07:49PM +0100, Thomas Gleixner wrote: > From: Thomas Gleixner > > The intel PEBS/BTS debug store is a design trainwreck as is expects virtual > addresses which must be visible in any execution context. Sure, what can possibly go wrong?! :-\ > So it is required to

[patch 43/60] x86/fixmap: Add debugstore entries to cpu_entry_area

2017-12-04 Thread Thomas Gleixner
From: Thomas Gleixner The intel PEBS/BTS debug store is a design trainwreck as is expects virtual addresses which must be visible in any execution context. So it is required to make these mappings visible to user space when kernel page table isolation is active. Provide

[patch 43/60] x86/fixmap: Add debugstore entries to cpu_entry_area

2017-12-04 Thread Thomas Gleixner
From: Thomas Gleixner The intel PEBS/BTS debug store is a design trainwreck as is expects virtual addresses which must be visible in any execution context. So it is required to make these mappings visible to user space when kernel page table isolation is active. Provide enough room for the