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Re: [Public WebGL] EXT_disjoint_timer_query disabled



My guess is the extension has been disabled due to recently discovered "GLitch" rowhammer attack vector.

> EXT_DISJOINT_TIMER_QUERY is an OpenGL extension developed to provide developers with more detailed information about the performance of their applications [46]. This extension, if made available to the system by the GPU driver, is accessible from both WebGL and WebGL2, and provides the _javascript_ runtime with two timing sources: (1) TIME_ELAPSED_EXT and (2) TIMESTAMP_EXT. Such timers allow an attacker to measure the timing of secret operations (e.g., memory accesses) performed either by the CPU or the GPU.

On Sun, May 13, 2018 at 4:32 PM Florian Bösch <pyalot@gmail.com> wrote:
On Fri, Apr 6, 2018 at 12:50 AM, Ken Russell <kbr@google.com> wrote:
We can not currently discuss why the extension has been disabled. We should be able to do so in about a month.

It's now been a month and a week since this statement.