From mboxrd@z Thu Jan 1 00:00:00 1970 From: james.morse@arm.com (James Morse) Date: Fri, 28 Jul 2017 15:10:07 +0100 Subject: [PATCH v2 04/16] arm64: entry.S: mask all exceptions during kernel_exit In-Reply-To: <20170728141019.9084-1-james.morse@arm.com> References: <20170728141019.9084-1-james.morse@arm.com> Message-ID: <20170728141019.9084-5-james.morse@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Add a disable_daif call to kernel_exit to mask all exceptions before restoring registers that are overwritten by an exception. This should be done before we restore sp_el0, as any exception taken from EL1 will assume this register is set correctly. After this patch it is no longer necessary to mask interrupts before kernel_exit. Signed-off-by: James Morse --- arch/arm64/kernel/entry.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index b738880350f9..491182f0abb5 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -207,6 +207,8 @@ alternative_else_nop_endif 2: #endif + disable_daif + .if \el == 0 ldr x23, [sp, #S_SP] // load return stack pointer msr sp_el0, x23 @@ -438,8 +440,6 @@ el1_da: mov x2, sp // struct pt_regs bl do_mem_abort - // disable interrupts before pulling preserved data off the stack - disable_irq kernel_exit 1 el1_sp_pc: /* -- 2.13.2