On 2024-08-27 00:36, Charlie Jenkins wrote:
I tested this patch on 6.10.2 kernel and could confirm that it fixes the crash of chromium. But I think I prefer Yangyu Chen's approach because that would avoid breaking some applications on sv57.The hint address should not forcefully restrict the addresses returned by mmap as this causes mmap to report ENOMEM when there is memory still available. Signed-off-by: Charlie Jenkins <charlie@xxxxxxxxxxxx> Fixes: b5b4287accd7 ("riscv: mm: Use hint address in mmap if available") Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57") Closes: https://lore.kernel.org/linux-kernel/ZbxTNjQPFKBatMq+@ghost/T/#mccb1890466bf5a488c9ce7441e57e42271895765 --- arch/riscv/include/asm/processor.h | 26 ++------------------------ 1 file changed, 2 insertions(+), 24 deletions(-) diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index 8702b8721a27..efa1b3519b23 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -14,36 +14,14 @@#include <asm/ptrace.h> -/*- * addr is a hint to the maximum userspace address that mmap should provide, so - * this macro needs to return the largest address space available so that - * mmap_end < addr, being mmap_end the top of that address space. - * See Documentation/arch/riscv/vm-layout.rst for more details. - */ #define arch_get_mmap_end(addr, len, flags) \ ({ \ - unsigned long mmap_end; \ - typeof(addr) _addr = (addr); \ - if ((_addr) == 0 || is_compat_task() || \ - ((_addr + len) > BIT(VA_BITS - 1))) \ - mmap_end = STACK_TOP_MAX; \ - else \ - mmap_end = (_addr + len); \ - mmap_end; \ + STACK_TOP_MAX; \ })#define arch_get_mmap_base(addr, base) \({ \ - unsigned long mmap_base; \ - typeof(addr) _addr = (addr); \ - typeof(base) _base = (base); \ - unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base); \ - if ((_addr) == 0 || is_compat_task() || \ - ((_addr + len) > BIT(VA_BITS - 1))) \ - mmap_base = (_base); \ - else \ - mmap_base = (_addr + len) - rnd_gap; \ - mmap_base; \ + base; \ })#ifdef CONFIG_64BIT
Tested-by: Levi Zim <rsworktech@xxxxxxxxxxx> # Chromium, sv39
