4.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Max Filippov <jcmvbkbc@xxxxxxxxx> commit 5029615e25dc5040beb065f36743c127a8e51497 upstream. Build-time fixes: - make lbeg/lend/lcount save/restore conditional on kernel entry; - don't clear lcount in platform_restart functions unconditionally. Run-time fixes: - use correct end of range register in __endla paired with __loopt, not the unused temporary register. This fixes .bss zero-initialization. Update comments in asmmacro.h; - don't clobber a10 in the usercopy that leads to access to unmapped memory. Signed-off-by: Max Filippov <jcmvbkbc@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/xtensa/include/asm/asmmacro.h | 7 ++++--- arch/xtensa/kernel/entry.S | 8 ++++++-- arch/xtensa/kernel/head.S | 2 +- arch/xtensa/lib/usercopy.S | 6 +++--- arch/xtensa/platforms/iss/setup.c | 2 ++ arch/xtensa/platforms/xt2000/setup.c | 2 ++ arch/xtensa/platforms/xtfpga/setup.c | 2 ++ 7 files changed, 20 insertions(+), 9 deletions(-) --- a/arch/xtensa/include/asm/asmmacro.h +++ b/arch/xtensa/include/asm/asmmacro.h @@ -35,9 +35,10 @@ * __loop as * restart loop. 'as' register must not have been modified! * - * __endla ar, at, incr + * __endla ar, as, incr * ar start address (modified) - * as scratch register used by macro + * as scratch register used by __loops/__loopi macros or + * end address used by __loopt macro * inc increment */ @@ -97,7 +98,7 @@ .endm /* - * loop from ar to ax + * loop from ar to as */ .macro __loopt ar, as, at, incr_log2 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -367,8 +367,10 @@ common_exception: s32i a2, a1, PT_SYSCALL movi a2, 0 s32i a3, a1, PT_EXCVADDR +#if XCHAL_HAVE_LOOPS xsr a2, lcount s32i a2, a1, PT_LCOUNT +#endif /* It is now save to restore the EXC_TABLE_FIXUP variable. */ @@ -429,11 +431,12 @@ common_exception: rsync # PS.WOE => rsync => overflow /* Save lbeg, lend */ - +#if XCHAL_HAVE_LOOPS rsr a4, lbeg rsr a3, lend s32i a4, a1, PT_LBEG s32i a3, a1, PT_LEND +#endif /* Save SCOMPARE1 */ @@ -724,13 +727,14 @@ common_exception_exit: wsr a3, sar /* Restore LBEG, LEND, LCOUNT */ - +#if XCHAL_HAVE_LOOPS l32i a2, a1, PT_LBEG l32i a3, a1, PT_LEND wsr a2, lbeg l32i a2, a1, PT_LCOUNT wsr a3, lend wsr a2, lcount +#endif /* We control single stepping through the ICOUNTLEVEL register. */ --- a/arch/xtensa/kernel/head.S +++ b/arch/xtensa/kernel/head.S @@ -249,7 +249,7 @@ ENTRY(_startup) __loopt a2, a3, a4, 2 s32i a0, a2, 0 - __endla a2, a4, 4 + __endla a2, a3, 4 #if XCHAL_DCACHE_IS_WRITEBACK --- a/arch/xtensa/lib/usercopy.S +++ b/arch/xtensa/lib/usercopy.S @@ -222,8 +222,8 @@ __xtensa_copy_user: loopnez a7, .Loop2done #else /* !XCHAL_HAVE_LOOPS */ beqz a7, .Loop2done - slli a10, a7, 4 - add a10, a10, a3 # a10 = end of last 16B source chunk + slli a12, a7, 4 + add a12, a12, a3 # a12 = end of last 16B source chunk #endif /* !XCHAL_HAVE_LOOPS */ .Loop2: EX(l32i, a7, a3, 4, l_fixup) @@ -241,7 +241,7 @@ __xtensa_copy_user: EX(s32i, a9, a5, 12, s_fixup) addi a5, a5, 16 #if !XCHAL_HAVE_LOOPS - blt a3, a10, .Loop2 + blt a3, a12, .Loop2 #endif /* !XCHAL_HAVE_LOOPS */ .Loop2done: bbci.l a4, 3, .L12 --- a/arch/xtensa/platforms/iss/setup.c +++ b/arch/xtensa/platforms/iss/setup.c @@ -61,7 +61,9 @@ void platform_restart(void) #if XCHAL_NUM_IBREAK > 0 "wsr a2, ibreakenable\n\t" #endif +#if XCHAL_HAVE_LOOPS "wsr a2, lcount\n\t" +#endif "movi a2, 0x1f\n\t" "wsr a2, ps\n\t" "isync\n\t" --- a/arch/xtensa/platforms/xt2000/setup.c +++ b/arch/xtensa/platforms/xt2000/setup.c @@ -72,7 +72,9 @@ void platform_restart(void) #if XCHAL_NUM_IBREAK > 0 "wsr a2, ibreakenable\n\t" #endif +#if XCHAL_HAVE_LOOPS "wsr a2, lcount\n\t" +#endif "movi a2, 0x1f\n\t" "wsr a2, ps\n\t" "isync\n\t" --- a/arch/xtensa/platforms/xtfpga/setup.c +++ b/arch/xtensa/platforms/xtfpga/setup.c @@ -63,7 +63,9 @@ void platform_restart(void) #if XCHAL_NUM_IBREAK > 0 "wsr a2, ibreakenable\n\t" #endif +#if XCHAL_HAVE_LOOPS "wsr a2, lcount\n\t" +#endif "movi a2, 0x1f\n\t" "wsr a2, ps\n\t" "isync\n\t" -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html