From: Maciej W. Rozycki macro@orcam.me.uk
commit 244eae91a94c6dab82b3232967d10eeb9dfa21c6 upstream.
Recent tightening of the opcode table in binutils so as to consistently disallow the assembly or disassembly of CP0 instructions not supported by the processor architecture chosen has caused a regression like below:
arch/mips/dec/prom/locore.S: Assembler messages: arch/mips/dec/prom/locore.S:29: Error: opcode not supported on this processor: r4600 (mips3) `rfe'
in a piece of code used to probe for memory with PMAX DECstation models, which have non-REX firmware. Those computers always have an R2000 CPU and consequently the exception handler used in memory probing uses the RFE instruction, which those processors use.
While adding 64-bit support this code was correctly excluded for 64-bit configurations, however it should have also been excluded for irrelevant 32-bit configurations. Do this now then, and only enable PMAX memory probing for R3k systems.
Reported-by: Jan-Benedict Glaw jbglaw@lug-owl.de Reported-by: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Maciej W. Rozycki macro@orcam.me.uk Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org # v2.6.12+ Signed-off-by: Thomas Bogendoerfer tsbogend@alpha.franken.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/mips/dec/prom/Makefile | 2 +- arch/mips/include/asm/dec/prom.h | 15 +++++---------- 2 files changed, 6 insertions(+), 11 deletions(-)
--- a/arch/mips/dec/prom/Makefile +++ b/arch/mips/dec/prom/Makefile @@ -5,4 +5,4 @@
lib-y += init.o memory.o cmdline.o identify.o console.o
-lib-$(CONFIG_32BIT) += locore.o +lib-$(CONFIG_CPU_R3000) += locore.o --- a/arch/mips/include/asm/dec/prom.h +++ b/arch/mips/include/asm/dec/prom.h @@ -47,16 +47,11 @@ */ #define REX_PROM_MAGIC 0x30464354
-#ifdef CONFIG_64BIT - -#define prom_is_rex(magic) 1 /* KN04 and KN05 are REX PROMs. */ - -#else /* !CONFIG_64BIT */ - -#define prom_is_rex(magic) ((magic) == REX_PROM_MAGIC) - -#endif /* !CONFIG_64BIT */ - +/* KN04 and KN05 are REX PROMs, so only do the check for R3k systems. */ +static inline bool prom_is_rex(u32 magic) +{ + return !IS_ENABLED(CONFIG_CPU_R3000) || magic == REX_PROM_MAGIC; +}
/* * 3MIN/MAXINE PROM entry points for DS5000/1xx's, DS5000/xx's and