diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index cf006d40342c..36586dba6fa6 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1186,6 +1186,15 @@ if !MMU source "arch/arm/Kconfig-nommu" endif +config ARM_ERRATA_326103 + bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory" + depends on CPU_V6 + help + Executing a SWP instruction to read-only memory does not set bit 11 + of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to + treat the access as a read, preventing a COW from occurring and + causing the faulting task to livelock. + config ARM_ERRATA_411920 bool "ARM errata: Invalidation of the Instruction Cache operation can fail" depends on CPU_V6 || CPU_V6K diff --git a/arch/arm/mm/abort-ev6.S b/arch/arm/mm/abort-ev6.S index ff1f7cc11f87..80741992a9fc 100644 --- a/arch/arm/mm/abort-ev6.S +++ b/arch/arm/mm/abort-ev6.S @@ -26,18 +26,23 @@ ENTRY(v6_early_abort) mrc p15, 0, r1, c5, c0, 0 @ get FSR mrc p15, 0, r0, c6, c0, 0 @ get FAR /* - * Faulty SWP instruction on 1136 doesn't set bit 11 in DFSR (erratum 326103). - * The test below covers all the write situations, including Java bytecodes + * Faulty SWP instruction on 1136 doesn't set bit 11 in DFSR. */ - bic r1, r1, #1 << 11 @ clear bit 11 of FSR - tst r5, #PSR_J_BIT @ Java? +#ifdef CONFIG_ARM_ERRATA_326103 + ldr ip, =0x4107b36 + mrc p15, 0, r3, c0, c0, 0 @ get processor id + teq ip, r3, lsr #4 @ r0 ARM1136? bne do_DataAbort - do_thumb_abort fsr=r1, pc=r4, psr=r5, tmp=r3 - ldreq r3, [r4] @ read aborted ARM instruction + tst r5, #PSR_J_BIT @ Java? + tsteq r5, #PSR_T_BIT @ Thumb? + bne do_DataAbort + bic r1, r1, #1 << 11 @ clear bit 11 of FSR + ldr r3, [r4] @ read aborted ARM instruction #ifdef CONFIG_CPU_ENDIAN_BE8 - reveq r3, r3 + rev r3, r3 #endif do_ldrd_abort tmp=ip, insn=r3 tst r3, #1 << 20 @ L = 0 -> write orreq r1, r1, #1 << 11 @ yes. +#endif b do_DataAbort