diff options
Diffstat (limited to 'arch/riscv')
| -rw-r--r-- | arch/riscv/include/asm/barrier.h | 10 | ||||
| -rw-r--r-- | arch/riscv/mm/init.c | 2 |
2 files changed, 10 insertions, 2 deletions
diff --git a/arch/riscv/include/asm/barrier.h b/arch/riscv/include/asm/barrier.h index 3f1737f301cc..d0e24aaa2aa0 100644 --- a/arch/riscv/include/asm/barrier.h +++ b/arch/riscv/include/asm/barrier.h @@ -58,8 +58,16 @@ do { \ * The AQ/RL pair provides a RCpc critical section, but there's not really any * way we can take advantage of that here because the ordering is only enforced * on that one lock. Thus, we're just doing a full fence. + * + * Since we allow writeX to be called from preemptive regions we need at least + * an "o" in the predecessor set to ensure device writes are visible before the + * task is marked as available for scheduling on a new hart. While I don't see + * any concrete reason we need a full IO fence, it seems safer to just upgrade + * this in order to avoid any IO crossing a scheduling boundary. In both + * instances the scheduler pairs this with an mb(), so nothing is necessary on + * the new hart. */ -#define smp_mb__after_spinlock() RISCV_FENCE(rw,rw) +#define smp_mb__after_spinlock() RISCV_FENCE(iorw,iorw) #include <asm-generic/barrier.h> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 319812923012..b1eb6a041118 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -115,9 +115,9 @@ void __init setup_bootmem(void) /* Reserve from the start of the kernel to the end of the kernel */ memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); - set_max_mapnr(PFN_DOWN(mem_size)); max_pfn = PFN_DOWN(memblock_end_of_DRAM()); max_low_pfn = max_pfn; + set_max_mapnr(max_low_pfn); #ifdef CONFIG_BLK_DEV_INITRD setup_initrd(); |