+ others On Fri, Mar 04, 2016 at 04:02:25PM -0800, Brian Norris wrote: > Hi Arnd, > > I know you're travelling, but... > > On Mon, Jan 25, 2016 at 04:41:50PM +0100, Arnd Bergmann wrote: > > When XIP_KERNEL is enabled, some functions are defined in the .data > > ELF section because we require them to be in RAM whenever we communicate > > with the flash chip. However this causes problems when FTRACE is > > enabled and gcc emits calls to __gnu_mcount_nc in the function > > prolog: > > > > drivers/built-in.o: In function `cfi_chip_setup': > > :(.data+0x272fc): relocation truncated to fit: R_ARM_CALL against symbol `__gnu_mcount_nc' defined in .text section in arch/arm/kernel/built-in.o > > drivers/built-in.o: In function `cfi_probe_chip': > > :(.data+0x27de8): relocation truncated to fit: R_ARM_CALL against symbol `__gnu_mcount_nc' defined in .text section in arch/arm/kernel/built-in.o > > /tmp/ccY172rP.s: Assembler messages: > > /tmp/ccY172rP.s:70: Warning: ignoring changed section attributes for .data > > /tmp/ccY172rP.s: Error: 1 warning, treating warnings as errors > > make[5]: *** [drivers/mtd/chips/cfi_probe.o] Error 1 > > /tmp/ccK4rjeO.s: Assembler messages: > > /tmp/ccK4rjeO.s:421: Warning: ignoring changed section attributes for .data > > /tmp/ccK4rjeO.s: Error: 1 warning, treating warnings as errors > > make[5]: *** [drivers/mtd/chips/cfi_util.o] Error 1 > > /tmp/ccUvhCYR.s: Assembler messages: > > /tmp/ccUvhCYR.s:1895: Warning: ignoring changed section attributes for .data > > /tmp/ccUvhCYR.s: Error: 1 warning, treating warnings as errors > > Can you provide a sample .config that DOES build correctly with > XIP_KERNEL enabled + this patch? My first attempt yields some other > failures I don't care to fixup right now... Particularly, mach-pxa MTD_XIP looks like it's broken, at least since here: 5d284e353eb1 ARM: pxa: avoid accessing interrupt registers directly CC drivers/mtd/chips/cfi_cmdset_0002.o drivers/mtd/chips/cfi_cmdset_0002.c: In function ‘xip_udelay’: drivers/mtd/chips/cfi_cmdset_0002.c:962:35: warning: initialization makes integer from pointer without a cast [enabled by default] drivers/mtd/chips/cfi_cmdset_0002.c:967:8: error: ‘ICIP’ undeclared (first use in this function) drivers/mtd/chips/cfi_cmdset_0002.c:967:8: note: each undeclared identifier is reported only once for each function it appears in drivers/mtd/chips/cfi_cmdset_0002.c:967:15: error: ‘ICMR’ undeclared (first use in this function) drivers/mtd/chips/cfi_cmdset_0002.c:981:123: error: invalid operands to binary / (have ‘void *’ and ‘int’) drivers/mtd/chips/cfi_cmdset_0002.c:982:14: warning: assignment makes integer from pointer without a cast [enabled by default] drivers/mtd/chips/cfi_cmdset_0002.c:984:124: error: invalid operands to binary / (have ‘void *’ and ‘int’) drivers/mtd/chips/cfi_cmdset_0002.c:1034:10: warning: assignment makes integer from pointer without a cast [enabled by default] drivers/mtd/chips/cfi_cmdset_0002.c:1045:118: error: invalid operands to binary / (have ‘void *’ and ‘int’) Looks like arch/arm/mach-pxa/include/mach/mtd-xip.h can't find ICIP or ICMR... > Anyway, I don't doubt you have a good fix here, so I can probably take > it. Any review from others would be welcome though. > > > Specifically, this does not work because the .data section is not > > marked executable, which leads LD to not generate trampolines for > > long calls. > > > > This moves the __xipram functions into their own .xiptext section instead. > > The section is still placed next to .data and located in RAM but is marked > > executable, which avoids the build errors. > > > > Also, we only need to place the XIP functions into a separate section > > if both CONFIG_XIP_KERNEL and CONFIG_MTD_XIP are set: When only MTD_XIP > > is used, the whole kernel is still in RAM and we do not need to worry > > about pulling out the rug under it. When only XIP_KERNEL but not MTD_XIP > > is set, the kernel is in some form of ROM, but we never write to it. > > > > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Brian -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
