Unverified Commit 0c710050 authored by Zhe Qiao's avatar Zhe Qiao Committed by Palmer Dabbelt
Browse files

riscv/mm: Add handling for VM_FAULT_SIGSEGV in mm_fault_error() 



Handle VM_FAULT_SIGSEGV in the page fault path so that we correctly
kill the process and we don't BUG() the kernel.

Fixes: 07037db5 ("RISC-V: Paging and MMU")
Signed-off-by: default avatarZhe Qiao <qiaozhe@iscas.ac.cn>
Reviewed-by: default avatarAlexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240731084547.85380-1-qiaozhe@iscas.ac.cn


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 941a8e9b

arch/riscv/mm/fault.c

+9 −8
Original line number Diff line number Diff line
@@ -61,26 +61,27 @@ static inline void no_context(struct pt_regs *regs, unsigned long addr) 


static inline void mm_fault_error(struct pt_regs *regs, unsigned long addr, vm_fault_t fault)

{

	if (!user_mode(regs)) {

		no_context(regs, addr);

		return;

	}



	if (fault & VM_FAULT_OOM) {

		/*

		 * We ran out of memory, call the OOM killer, and return the userspace

		 * (which will retry the fault, or kill us if we got oom-killed).

		 */

		if (!user_mode(regs)) {

			no_context(regs, addr);

			return;

		}

		pagefault_out_of_memory();

		return;

	} else if (fault & (VM_FAULT_SIGBUS | VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE)) {

		/* Kernel mode? Handle exceptions or die */

		if (!user_mode(regs)) {

			no_context(regs, addr);

			return;

		}

		do_trap(regs, SIGBUS, BUS_ADRERR, addr);

		return;

	} else if (fault & VM_FAULT_SIGSEGV) {

		do_trap(regs, SIGSEGV, SEGV_MAPERR, addr);

		return;

	}



	BUG();

}