riscv: mm: Fixup compat mode boot failure
authorGuo Ren <guoren@linux.alibaba.com>
Fri, 22 Dec 2023 11:57:00 +0000 (06:57 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 1 Feb 2024 00:18:55 +0000 (16:18 -0800)
commiteab6917e1016bb8ef1b353ef873908ee641efa44
tree015cb5523bbd55d6b05fbb30aa710262f7a5bc80
parent724103429a2d0a1f6b201bbc0866a410098c164e
riscv: mm: Fixup compat mode boot failure

commit 5f449e245e5b0d9d63eef6c8968fbdc3a8594407 upstream.

In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
will cause a user segment fault. Sometimes, it would cause boot
failure when the whole rootfs is rv32.

Freeing unused kernel image (initmem) memory: 2236K
Run /sbin/init as init process
Starting init: /sbin/init exists but couldn't execute it (error -14)
Run /etc/init as init process
...

Increase the TASK_SIZE to cover STACK_TOP.

Cc: stable@vger.kernel.org
Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20231222115703.2404036-2-guoren@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/riscv/include/asm/pgtable.h