Unverified Commit 5f449e24 authored by Guo Ren's avatar Guo Ren Committed by Palmer Dabbelt
Browse files

riscv: mm: Fixup compat mode boot failure 



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: add2cc6b ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
Signed-off-by: default avatarGuo Ren <guoren@linux.alibaba.com>
Signed-off-by: default avatarGuo Ren <guoren@kernel.org>
Reviewed-by: default avatarLeonardo Bras <leobras@redhat.com>
Reviewed-by: default avatarCharlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20231222115703.2404036-2-guoren@kernel.org


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent b85ea95d

arch/riscv/include/asm/pgtable.h

+1 −1
Original line number Diff line number Diff line
@@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte) 
#define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)



#ifdef CONFIG_COMPAT

#define TASK_SIZE_32	(_AC(0x80000000, UL) - PAGE_SIZE)

#define TASK_SIZE_32	(_AC(0x80000000, UL))

#define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \

			 TASK_SIZE_32 : TASK_SIZE_64)

#else