Clear the IT state when invoking a Thumb-2 signal handler (d71e1352) · Commits · 戴 / test

If a process is interrupted during an If-Then block and a signal is invoked, the ITSTATE bits must be cleared otherwise the handler would not run correctly. Signed-off-by:

Catalin Marinas <catalin.marinas@arm.com> Cc: Joseph S. Myers <joseph@codesourcery.com>

arch/arm/include/asm/ptrace.h

+7 −0

Original line number	Diff line number	Diff line
		@@ -65,6 +65,13 @@
		#define PSR_x 0x0000ff00 /* Extension */
		#define PSR_c 0x000000ff /* Control */

		/*
		* ARMv7 groups of APSR bits
		*/
		#define PSR_ISET_MASK 0x01000010 /* ISA state (J, T) mask */
		#define PSR_IT_MASK 0x0600fc00 /* If-Then execution state mask */
		#define PSR_ENDIAN_MASK 0x00000200 /* Endianness state mask */

		#ifndef __ASSEMBLY__

		/*

arch/arm/kernel/signal.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -426,9 +426,13 @@ setup_return(struct pt_regs regs, struct k_sigaction ka,
		*/
		thumb = handler & 1;

		if (thumb)
		if (thumb) {
		cpsr \|= PSR_T_BIT;
		else
		#if __LINUX_ARM_ARCH__ >= 7
		/* clear the If-Then Thumb-2 execution state */
		cpsr &= ~PSR_IT_MASK;
		#endif
		} else
		cpsr &= ~PSR_T_BIT;
		}
		#endif

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