Nicholas Piggin's on August 27, 2019 8:20 pm: > Christophe Leroy's on August 27, 2019 4:13 pm: >> >> >> Le 27/08/2019 à 05:30, Nicholas Piggin a écrit : >>> There is support for the kernel to execute the 'sc 0' instruction and >>> make a system call to itself. This is a relic that is unused in the >>> tree, therefore untested. It's also highly questionable for modules to >>> be doing this. >> >> I like it. >> >> I dropped support for that in PPC32 when I added fast-path syscalls. > > Good, then we'll match again. > >>> - beq 2f /* if from kernel mode */ >>> #ifdef CONFIG_PPC_FSL_BOOK3E >>> START_BTB_FLUSH_SECTION >>> BTB_FLUSH(r10) >>> END_BTB_FLUSH_SECTION >>> #endif >>> ACCOUNT_CPU_USER_ENTRY(r13, r10, r11) >>> -2: std r2,GPR2(r1) > > Btw. there is a hunk which restores this optimisation but it leaked > into a later patch, I'll move it back here.
I'm wrong. Now I look at it again, the hunk should be removed completely of course. Thanks, Nick
