On Thu, 2018-11-08 at 18:52 +0100, Christophe LEROY wrote: > > In signal_32.c and signal_64.c, save_user_regs() calls __put_user() to > modify code, then calls flush_icache_range() on user addresses. > > Shouldn't flush_icache_range() be performed with userspace access > protection unlocked ?
Thankfully this code is pretty much never used these days... Russell: To trigger that, you need to disable the VDSO. This brings back the idea however of having a way to "bulk" open the gate during the whole signal sequence... Cheers, Ben.