WebSetting TSD Bit in CR4 causes crash. I want to restrict the usage of the rdtsc instruction such that it can only be executed when in ring 0. According to the Intel Manuals this is … http://old-list-archives.xenproject.org/archives/html/xen-devel/2007-10/msg00932.html
Linux-Kernel Archive: [PATCH 21/55] KVM: Portability: Move …
Web*tip: x86/iopl] x86/cpu: Unify cpu_init() @ 2024-11-16 11:51 tip-bot2 for Thomas Gleixner 0 siblings, 0 replies; 2+ messages in thread From: tip-bot2 for Thomas Gleixner @ 2024-11-16 11:51 UTC (permalink / raw) To: linux-tip-commits Cc: Thomas Gleixner, Andy Lutomirski, Ingo Molnar, Borislav Petkov, linux-kernel The following commit has been ... Web2)RDTSC can become priviledged by setting CR4.TSD flag: We can get an access violation if this instruction is used 3) Attacker cannot spend much time between RDTSC because execution time on multi core CPUs depend on things attacker cannot observe. => wait too long, too much noise to pick up signal. 4) When Clflush actually flushes an address a ... red cross class coupon
TSD – Short Time Delay Setting - CR4 Discussion Thread
WebDec 14, 2011 · Re: tsd – Short time delay setting. In any MCCB, the short time delay setting is the intentional time delay set so that the MCCB operates only after the set time delay, … WebApr 12, 2013 · Or the use of this instruction is disabled via CR4.TSD=0. – Alexey Frunze. Apr 12, 2013 at 9:46 @AlexeyFrunze: It's a Merom-L CPU, and predates Core i7. – NPE. Apr 12, 2013 at 9:48 @NPE Oh, I just tried this too and it seems to work. WebDisabling user-space RDTSC (setting CR4.TSD) seems evil and pointless. At least some users of it (the perfctr library and I hope eventually also perfmon2) do use it in an SMP-safe manner (through special user/kernel protocols). /Mikael-To unsubscribe from this list: send the line "unsubscribe linux-kernel" in knights of columbus shiner tx