Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-16 Thread Alexander Graf
On 13.11.20 16:55, Joel Fernandes wrote: +static enum coresched_cmds coresched_cmd __ro_after_init = CORE_SCHED_SECURE; + +static int __init coresched_parse_cmdline(char *arg) +{ + if (!strcmp(arg, "off")) + coresched_cmd = CORE_SCHED_OFF; + else if (!strcmp(arg, "

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-13 Thread Joel Fernandes
> > +static enum coresched_cmds coresched_cmd __ro_after_init = > > CORE_SCHED_SECURE; > > + > > +static int __init coresched_parse_cmdline(char *arg) > > +{ > > + if (!strcmp(arg, "off")) > > + coresched_cmd = CORE_SCHED_OFF; > > + else if (!strcmp(arg, "on")) > > +

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-12 Thread Alexander Graf
On 12.11.20 15:40, Joel Fernandes wrote: On Thu, Nov 12, 2020 at 08:40:05AM -0500, Joel Fernandes wrote: On Wed, Nov 11, 2020 at 11:29:37PM +0100, Alexander Graf wrote: On 11.11.20 23:15, Joel Fernandes wrote: On Wed, Nov 11, 2020 at 5:13 PM Joel Fernandes wrote: On Wed, Nov 11, 2020

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-12 Thread Alexander Graf
On 12.11.20 16:28, Joel Fernandes wrote: On Thu, Nov 12, 2020 at 03:52:32PM +0100, Alexander Graf wrote: On 12.11.20 14:40, Joel Fernandes wrote: On Wed, Nov 11, 2020 at 11:29:37PM +0100, Alexander Graf wrote: On 11.11.20 23:15, Joel Fernandes wrote: On Wed, Nov 11, 2020 at 5:13 PM

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-12 Thread Joel Fernandes
On Thu, Nov 12, 2020 at 03:52:32PM +0100, Alexander Graf wrote: > > > On 12.11.20 14:40, Joel Fernandes wrote: > > > > On Wed, Nov 11, 2020 at 11:29:37PM +0100, Alexander Graf wrote: > > > > > > > > > On 11.11.20 23:15, Joel Fernandes wrote: > > > > > > > > On Wed, Nov 11, 2020 at 5:13 PM Joe

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-12 Thread Alexander Graf
On 12.11.20 14:40, Joel Fernandes wrote: On Wed, Nov 11, 2020 at 11:29:37PM +0100, Alexander Graf wrote: On 11.11.20 23:15, Joel Fernandes wrote: On Wed, Nov 11, 2020 at 5:13 PM Joel Fernandes wrote: On Wed, Nov 11, 2020 at 5:00 PM Alexander Graf wrote: On 11.11.20 22:14, Joel Ferna

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-12 Thread Joel Fernandes
On Thu, Nov 12, 2020 at 08:40:05AM -0500, Joel Fernandes wrote: > On Wed, Nov 11, 2020 at 11:29:37PM +0100, Alexander Graf wrote: > > > > > > On 11.11.20 23:15, Joel Fernandes wrote: > > > > > > On Wed, Nov 11, 2020 at 5:13 PM Joel Fernandes > > > wrote: > > > > > > > > On Wed, Nov 11, 2020 a

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-12 Thread Joel Fernandes
On Wed, Nov 11, 2020 at 11:29:37PM +0100, Alexander Graf wrote: > > > On 11.11.20 23:15, Joel Fernandes wrote: > > > > On Wed, Nov 11, 2020 at 5:13 PM Joel Fernandes > > wrote: > > > > > > On Wed, Nov 11, 2020 at 5:00 PM Alexander Graf wrote: > > > > On 11.11.20 22:14, Joel Fernandes wrote:

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-11 Thread Alexander Graf
On 11.11.20 23:15, Joel Fernandes wrote: On Wed, Nov 11, 2020 at 5:13 PM Joel Fernandes wrote: On Wed, Nov 11, 2020 at 5:00 PM Alexander Graf wrote: On 11.11.20 22:14, Joel Fernandes wrote: Some hardware such as certain AMD variants don't have cross-HT MDS/L1TF issues. Detect this and do

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-11 Thread Joel Fernandes
On Wed, Nov 11, 2020 at 5:13 PM Joel Fernandes wrote: > > On Wed, Nov 11, 2020 at 5:00 PM Alexander Graf wrote: > > On 11.11.20 22:14, Joel Fernandes wrote: > > >> Some hardware such as certain AMD variants don't have cross-HT MDS/L1TF > > >> issues. Detect this and don't enable core scheduling a

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-11 Thread Joel Fernandes
On Wed, Nov 11, 2020 at 5:00 PM Alexander Graf wrote: > > > > On 11.11.20 22:14, Joel Fernandes wrote: > > > > Sorry, forgot to CC +Tom Lendacky . Please take a look Tom, thanks. > > > > On Wed, Nov 11, 2020 at 4:10 PM Joel Fernandes (Google) > > wrote: > >> > >> Some hardware such as certain AMD

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-11 Thread Alexander Graf
On 11.11.20 22:14, Joel Fernandes wrote: Sorry, forgot to CC +Tom Lendacky . Please take a look Tom, thanks. On Wed, Nov 11, 2020 at 4:10 PM Joel Fernandes (Google) wrote: Some hardware such as certain AMD variants don't have cross-HT MDS/L1TF issues. Detect this and don't enable core sche

Re: [RFC 1/2] x86/bugs: Disable coresched on hardware that does not need it

2020-11-11 Thread Joel Fernandes
Sorry, forgot to CC +Tom Lendacky . Please take a look Tom, thanks. On Wed, Nov 11, 2020 at 4:10 PM Joel Fernandes (Google) wrote: > > Some hardware such as certain AMD variants don't have cross-HT MDS/L1TF > issues. Detect this and don't enable core scheduling as it can > needlessly slow the dev