Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-19 Thread Jan Beulich
On 19.04.2023 17:57, Roger Pau Monné wrote: > On Wed, Apr 19, 2023 at 04:39:01PM +0200, Jan Beulich wrote: >> On 19.04.2023 15:36, Roger Pau Monné wrote: >>> On Wed, Apr 19, 2023 at 02:00:38PM +0200, Jan Beulich wrote: On 19.04.2023 13:44, Roger Pau Monné wrote: > On Wed, Apr 19, 2023 at 1

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-19 Thread Roger Pau Monné
On Wed, Apr 19, 2023 at 04:39:01PM +0200, Jan Beulich wrote: > On 19.04.2023 15:36, Roger Pau Monné wrote: > > On Wed, Apr 19, 2023 at 02:00:38PM +0200, Jan Beulich wrote: > >> On 19.04.2023 13:44, Roger Pau Monné wrote: > >>> On Wed, Apr 19, 2023 at 10:43:22AM +0200, Jan Beulich wrote: > On 1

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-19 Thread Jan Beulich
On 19.04.2023 15:36, Roger Pau Monné wrote: > On Wed, Apr 19, 2023 at 02:00:38PM +0200, Jan Beulich wrote: >> On 19.04.2023 13:44, Roger Pau Monné wrote: >>> On Wed, Apr 19, 2023 at 10:43:22AM +0200, Jan Beulich wrote: On 19.04.2023 10:25, Roger Pau Monné wrote: > On Wed, Apr 19, 2023 at 0

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-19 Thread Roger Pau Monné
On Wed, Apr 19, 2023 at 02:00:38PM +0200, Jan Beulich wrote: > On 19.04.2023 13:44, Roger Pau Monné wrote: > > On Wed, Apr 19, 2023 at 10:43:22AM +0200, Jan Beulich wrote: > >> On 19.04.2023 10:25, Roger Pau Monné wrote: > >>> On Wed, Apr 19, 2023 at 08:17:45AM +0200, Jan Beulich wrote: > On 1

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-19 Thread Jan Beulich
On 19.04.2023 13:44, Roger Pau Monné wrote: > On Wed, Apr 19, 2023 at 10:43:22AM +0200, Jan Beulich wrote: >> On 19.04.2023 10:25, Roger Pau Monné wrote: >>> On Wed, Apr 19, 2023 at 08:17:45AM +0200, Jan Beulich wrote: On 18.04.2023 15:06, Roger Pau Monné wrote: > On Tue, Apr 18, 2023 at 0

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-19 Thread Roger Pau Monné
On Wed, Apr 19, 2023 at 10:43:22AM +0200, Jan Beulich wrote: > On 19.04.2023 10:25, Roger Pau Monné wrote: > > On Wed, Apr 19, 2023 at 08:17:45AM +0200, Jan Beulich wrote: > >> On 18.04.2023 15:06, Roger Pau Monné wrote: > >>> On Tue, Apr 18, 2023 at 01:00:53PM +0200, Jan Beulich wrote: > On 1

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-19 Thread Jan Beulich
On 19.04.2023 10:25, Roger Pau Monné wrote: > On Wed, Apr 19, 2023 at 08:17:45AM +0200, Jan Beulich wrote: >> On 18.04.2023 15:06, Roger Pau Monné wrote: >>> On Tue, Apr 18, 2023 at 01:00:53PM +0200, Jan Beulich wrote: On 18.04.2023 11:24, Roger Pau Monne wrote: > --- a/xen/arch/x86/includ

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-19 Thread Roger Pau Monné
On Wed, Apr 19, 2023 at 08:17:45AM +0200, Jan Beulich wrote: > On 18.04.2023 15:06, Roger Pau Monné wrote: > > On Tue, Apr 18, 2023 at 01:00:53PM +0200, Jan Beulich wrote: > >> On 18.04.2023 11:24, Roger Pau Monne wrote: > >>> --- a/xen/arch/x86/include/asm/config.h > >>> +++ b/xen/arch/x86/include

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-18 Thread Jan Beulich
On 18.04.2023 15:06, Roger Pau Monné wrote: > On Tue, Apr 18, 2023 at 01:00:53PM +0200, Jan Beulich wrote: >> On 18.04.2023 11:24, Roger Pau Monne wrote: >>> --- a/xen/arch/x86/include/asm/config.h >>> +++ b/xen/arch/x86/include/asm/config.h >>> @@ -44,6 +44,20 @@ >>> /* Linkage for x86 */ >>> #i

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-18 Thread Roger Pau Monné
On Tue, Apr 18, 2023 at 01:17:55PM +0100, Andrew Cooper wrote: > On 18/04/2023 10:24 am, Roger Pau Monne wrote: > > > diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S > > index 7675a59ff057..c204634910c4 100644 > > --- a/xen/arch/x86/x86_64/entry.S > > +++ b/xen/arch/x86/x86_

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-18 Thread Roger Pau Monné
On Tue, Apr 18, 2023 at 01:00:53PM +0200, Jan Beulich wrote: > On 18.04.2023 11:24, Roger Pau Monne wrote: > > Some of the assembly entry points cannot be safely patched until it's > > safe to use jmp, as livepatch can replace a whole block with a jmp to > > a new address, and that won't be safe un

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-18 Thread Andrew Cooper
On 18/04/2023 12:00 pm, Jan Beulich wrote: > On 18.04.2023 11:24, Roger Pau Monne wrote: >> Some of the assembly entry points cannot be safely patched until it's >> safe to use jmp, as livepatch can replace a whole block with a jmp to >> a new address, and that won't be safe until speculative mitig

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-18 Thread Andrew Cooper
On 18/04/2023 10:24 am, Roger Pau Monne wrote: > diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S > index 7675a59ff057..c204634910c4 100644 > --- a/xen/arch/x86/x86_64/entry.S > +++ b/xen/arch/x86/x86_64/entry.S > @@ -660,7 +660,7 @@ ENTRY(early_page_fault) > > ALI

Re: [PATCH] x86/livepatch: enable livepatching assembly source files

2023-04-18 Thread Jan Beulich
On 18.04.2023 11:24, Roger Pau Monne wrote: > Some of the assembly entry points cannot be safely patched until it's > safe to use jmp, as livepatch can replace a whole block with a jmp to > a new address, and that won't be safe until speculative mitigations > have been applied. Isn't the issue onl