Re: x86/clearregs: Register sanitizing at kernel entry for speculation hygiene

On Jan 9, 2018, at 5:34 PM, Andi Kleen wrote: >> I don't like this at all. Once upon a time, Linux syscalls were supposed to >> be fast. Then we learned about the Meltdown screwup, so we mostly fixed it >> for real upstream and the distroa seriously half-arsed their

Re: x86/clearregs: Register sanitizing at kernel entry for speculation hygiene

On Jan 9, 2018, at 5:34 PM, Andi Kleen wrote: >> I don't like this at all. Once upon a time, Linux syscalls were supposed to >> be fast. Then we learned about the Meltdown screwup, so we mostly fixed it >> for real upstream and the distroa seriously half-arsed their own fixes [1]. >>

Re: x86/clearregs: Register sanitizing at kernel entry for speculation hygiene

> I don't like this at all. Once upon a time, Linux syscalls were supposed to > be fast. Then we learned about the Meltdown screwup, so we mostly fixed it > for real upstream and the distroa seriously half-arsed their own fixes [1]. > This came with a big performance cost, but it can be

Re: x86/clearregs: Register sanitizing at kernel entry for speculation hygiene

> I don't like this at all. Once upon a time, Linux syscalls were supposed to > be fast. Then we learned about the Meltdown screwup, so we mostly fixed it > for real upstream and the distroa seriously half-arsed their own fixes [1]. > This came with a big performance cost, but it can be

Re: x86/clearregs: Register sanitizing at kernel entry for speculation hygiene

> On Jan 9, 2018, at 5:03 PM, Andi Kleen wrote: > > This patch kit implements clearing of all unused registers on kernel entries, > including system calls and all exceptions and interrupt. > > This doesn't fix any known issue, but will make it harder in general > to

Re: x86/clearregs: Register sanitizing at kernel entry for speculation hygiene

> On Jan 9, 2018, at 5:03 PM, Andi Kleen wrote: > > This patch kit implements clearing of all unused registers on kernel entries, > including system calls and all exceptions and interrupt. > > This doesn't fix any known issue, but will make it harder in general > to exploit the kernel with

x86/clearregs: Register sanitizing at kernel entry for speculation hygiene

This patch kit implements clearing of all unused registers on kernel entries, including system calls and all exceptions and interrupt. This doesn't fix any known issue, but will make it harder in general to exploit the kernel with speculation because it will be harder to get user controlled

x86/clearregs: Register sanitizing at kernel entry for speculation hygiene

This patch kit implements clearing of all unused registers on kernel entries, including system calls and all exceptions and interrupt. This doesn't fix any known issue, but will make it harder in general to exploit the kernel with speculation because it will be harder to get user controlled