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 PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 2 Nov 2017 11:32:38 +0100 From: Andy Lutomirski <luto@...capital.net> To: Ingo Molnar <mingo@...nel.org> Cc: Andy Lutomirski <luto@...nel.org>, X86 ML <x86@...nel.org>, Borislav Petkov <bpetkov@...e.de>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, Brian Gerst <brgerst@...il.com>, Dave Hansen <dave.hansen@...el.com>, Linus Torvalds <torvalds@...ux-foundation.org> Subject: Re: [PATCH v2 13/20] x86/asm/64: Pass sp0 directly to load_sp0() > On Nov 2, 2017, at 10:48 AM, Ingo Molnar <mingo@...nel.org> wrote: > > > * Andy Lutomirski <luto@...nel.org> wrote: > >> load_sp0() had an odd signature: >> >> void load_sp0(struct tss_struct *tss, struct thread_struct *thread); >> >> Simplify it to: >> >> void load_sp0(unsigned long sp0); > > I also added this to the changelog: > >> Also simplify a few get_cpu()/put_cpu() sequences to >> preempt_disable()/preempt_enable(). > > Plus: > >> --- a/arch/x86/kernel/cpu/common.c >> +++ b/arch/x86/kernel/cpu/common.c >> @@ -1572,7 +1572,7 @@ void cpu_init(void) >> initialize_tlbstate_and_flush(); >> enter_lazy_tlb(&init_mm, me); >> >> - load_sp0(t, ¤t->thread); >> + load_sp0(current->thread.sp0); >> set_tss_desc(cpu, t); >> load_TR_desc(); >> load_mm_ldt(&init_mm); >> @@ -1627,7 +1627,7 @@ void cpu_init(void) >> initialize_tlbstate_and_flush(); >> enter_lazy_tlb(&init_mm, curr); >> >> - load_sp0(t, thread); >> + load_sp0(thread->sp0); >> set_tss_desc(cpu, t); >> load_TR_desc(); >> load_mm_ldt(&init_mm); > > In the 32-bit path this was the last use of 'thread', making the local variable > unused - I removed it. > > Just curious: did you build/boot-test 32-bit kernels, or should we consider it > mostly untested? I tested it in an earlier version, but I'm away from my real computer, so I haven't tested as well as I should. It should be run through at least the selftests on 32-bit, 64-bit, and Xen PV. > > Thanks, > > Ingo
Powered by blists - more mailing lists