lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 11 May 2016 16:24:37 +0200 From: Paolo Bonzini <pbonzini@...hat.com> To: Andy Lutomirski <luto@...capital.net>, Borislav Petkov <bp@...e.de> Cc: Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>, X86 ML <x86@...nel.org>, Minfei Huang <mnghuan@...il.com>, Marcelo Tosatti <mtosatti@...hat.com>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, "H. Peter Anvin" <hpa@...or.com> Subject: Re: [PATCH] Cleanup __pvclock_read_cycles to remove useless variables On 30/04/2016 23:57, Andy Lutomirski wrote: >> > Should we kill __pvclock_read_cycles in favor of vread_pvclock? It looks >> > doable at a quick scan... >> > > The in-kernel version might have to be a bit different because it > needs to handle the !stable case. If !stable, it should just use the > current CPU's copy which means that, realistically, it should just > get_cpu and use the local copy unconditionally. Other than that, it > could look a lot like the vread_pvclock variant. > > But I agree, the current thing is incomprehensible. It also lacks smp_rmb()s. One is more or less implicit in rdtsc, but you need one to separate __pvclock_read_cycles's reads of src->foo from pvclock_read_flags's read of src->version. Minfei, would you like to take a look? Paolo
Powered by blists - more mailing lists