Re: Compiling kernel-3.4.xxx with gcc-9.x. Need some help.
From: Fawad Lateef
Date: Sun Mar 28 2021 - 17:04:34 EST
On Sun, 28 Mar 2021 at 22:49, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:
>
>
>
> On Sunday, March 28, 2021, Fawad Lateef <fawadlateef@xxxxxxxxx> wrote:
>>
>> Hi
>>
>> I am using an Olimex A20 SOM with NAND and due to some binary blob for
>> NAND driver, I am stuck with the sunxi kernel 3.4.xxx version. (Repo
>> here: https://github.com/linux-sunxi/linux-sunxi)
>>
>> I am currently using buildroot-2016 and gcc-5.5 for building the
>> kernel and every other package needed.
>>
>> Now the requirement is to move to the latest version of gcc-9.x, so
>> that we can have glibc++ provided by the gcc-9.1 toolchain.
>>
>> Main problem for moving to later versions of buildroot is the kernel
>> 3.4 which we couldn't to work with gcc-6 a few years ago _but_ now the
>> gcc-9.1 requirement is mandatory so now have to look into compiling
>> linux-3.4 with gcc-9.1 or above.
>>
>> Now I need some help.
>>
>> -- Is it realistic to expect 3.4 kernel compiling and boot
>> successfully with gcc-9.1?
>
>
> Pretty much, but i’m not sure the patches will be acceptable by upstream / stable.
Upstream patch is not really a concern as we are already running a
non-upstream kernel from sunxi.
>
>>
>> -- Secondly, till now I am able to compile until the point when its
>> going to generate the vmlinuz image, it failed with error at LD stage:
>> arm-none-linux-gnueabihf-ld: no machine record defined
>>
>> Last few lines from compile log:
>>
>> -------------------------------------------------------------------------------
>> include/linux/init.h:267:24: note: in expansion of macro ‘__initcall’
>> 267 | #define module_init(x) __initcall(x);
>> | ^~~~~~~~~~
>> net/sunrpc/auth_gss/auth_gss.c:1721:1: note: in expansion of macro ‘module_init’
>> 1721 | module_init(init_rpcsec_gss)
>> | ^~~~~~~~~~~
>> In file included from include/linux/kernel.h:20,
>> from include/linux/spinlock.h:55,
>> from include/linux/mmzone.h:7,
>> from include/linux/gfp.h:4,
>> from include/linux/slab.h:12,
>> from net/sunrpc/auth_gss/svcauth_gss.c:40:
>> include/linux/log2.h:22:1: warning: ignoring attribute ‘noreturn’
>> because it conflicts with attribute ‘const’ [-Wattributes]
>> 22 | int ____ilog2_NaN(void);
>> | ^~~
>> LD net/sunrpc/auth_gss/auth_rpcgss.o
>> LD net/sunrpc/auth_gss/built-in.o
>> LD net/sunrpc/built-in.o
>> LD net/built-in.o
>> LD vmlinux.o
>> MODPOST vmlinux.o
>> GEN .version
>> CHK include/generated/compile.h
>> UPD include/generated/compile.h
>> CC init/version.o
>> In file included from include/linux/kernel.h:20,
>> from include/linux/cache.h:4,
>> from include/linux/time.h:7,
>> from include/linux/stat.h:60,
>> from include/linux/module.h:10,
>> from init/version.c:10:
>> include/linux/log2.h:22:1: warning: ignoring attribute ‘noreturn’
>> because it conflicts with attribute ‘const’ [-Wattributes]
>> 22 | int ____ilog2_NaN(void);
>> | ^~~
>> LD init/built-in.o
>> LD .tmp_vmlinux1
>> arm-none-linux-gnueabihf-ld: no machine record defined
>> Makefile:875: recipe for target '.tmp_vmlinux1' failed
>> make: *** [.tmp_vmlinux1] Error 1
>> -------------------------------------------------------------------------------
>>
>>
>> After some investigation I found that the MACHINE_START macro from
>> arch/arm/include/asm/mach/arch.h is optimised by compiler and removed
>> from the object file during compilation of
>> "arch/arm/plat-sunxi/core.c" due to the error here:
>>
>> ---------------------------------------------------------------
>>
>> flateef@flateef-XPS-13-9360:~/src/tmp/linux-custom-venus-gc-9.2$ make
>> ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabihf- EXTRAVERSION=-custom1
>> uImage LOADADDR="0x40008000" -j4
>> CHK include/linux/version.h
>> CHK include/generated/utsrelease.h
>> make[1]: 'include/generated/mach-types.h' is up to date.
>> CALL scripts/checksyscalls.sh
>> CHK include/generated/compile.h
>> CC arch/arm/plat-sunxi/core.o
>> In file included from include/linux/kernel.h:20,
>> from arch/arm/plat-sunxi/core.c:20:
>> include/linux/log2.h:22:1: warning: ignoring attribute ‘noreturn’
>> because it conflicts with attribute ‘const’ [-Wattributes]
>> 22 | int ____ilog2_NaN(void);
>> | ^~~
>> In file included from include/linux/scatterlist.h:10,
>> from include/linux/dma-mapping.h:9,
>> from arch/arm/plat-sunxi/core.c:24:
>> arch/arm/plat-sunxi/core.c: In function ‘sw_irq_unmask’:
>> arch/arm/plat-sunxi/core.c:287:14: warning: left shift count >= width
>> of type [-Wshift-count-overflow]
>> 287 | writel((1 << SW_INT_IRQNO_ENMI), SW_INT_IRQ_PENDING_REG0);
>> | ^~
>> /home/flateef/src/tmp/linux-custom-venus-gc-9.2/arch/arm/include/asm/io.h:52:88:
>> note: in definition of macro ‘__raw_writel’
>> 52 | #define __raw_writel(v,a) (__chk_io_ptr(a), *(volatile
>> unsigned int __force *)(a) = (v))
>> |
>> ^
>> include/linux/byteorder/generic.h:87:21: note: in expansion of macro
>> ‘__cpu_to_le32’
>> 87 | #define cpu_to_le32 __cpu_to_le32
>> | ^~~~~~~~~~~~~
>> /home/flateef/src/tmp/linux-custom-venus-gc-9.2/arch/arm/include/asm/io.h:244:36:
>> note: in expansion of macro ‘writel_relaxed’
>> 244 | #define writel(v,c) ({ __iowmb(); writel_relaxed(v,c); })
>> | ^~~~~~~~~~~~~~
>> arch/arm/plat-sunxi/core.c:287:4: note: in expansion of macro ‘writel’
>> 287 | writel((1 << SW_INT_IRQNO_ENMI), SW_INT_IRQ_PENDING_REG0);
>> | ^~~~~~
>> In file included from arch/arm/plat-sunxi/core.c:53:
>> At top level:
>> /home/flateef/src/tmp/linux-custom-venus-gc-9.2/arch/arm/include/asm/mach/arch.h:69:34:
>> warning: ‘__mach_desc_SUN7I’ defined but not used
>> [-Wunused-const-variable=]
>> 69 | static const struct machine_desc __mach_desc_##_type \
>> | ^~~~~~~~~~~~
>> arch/arm/plat-sunxi/core.c:424:1: note: in expansion of macro ‘MACHINE_START’
>> 424 | MACHINE_START(SUN7I, "sun7i")
>> | ^~~~~~~~~~~~~
>> /home/flateef/src/tmp/linux-custom-venus-gc-9.2/arch/arm/include/asm/mach/arch.h:69:34:
>> warning: ‘__mach_desc_SUN5I’ defined but not used
>> [-Wunused-const-variable=]
>> 69 | static const struct machine_desc __mach_desc_##_type \
>> | ^~~~~~~~~~~~
>> arch/arm/plat-sunxi/core.c:410:1: note: in expansion of macro ‘MACHINE_START’
>> 410 | MACHINE_START(SUN5I, "sun5i")
>> | ^~~~~~~~~~~~~
>> /home/flateef/src/tmp/linux-custom-venus-gc-9.2/arch/arm/include/asm/mach/arch.h:69:34:
>> warning: ‘__mach_desc_SUN4I’ defined but not used
>> [-Wunused-const-variable=]
>> 69 | static const struct machine_desc __mach_desc_##_type \
>> | ^~~~~~~~~~~~
>> arch/arm/plat-sunxi/core.c:396:1: note: in expansion of macro ‘MACHINE_START’
>> 396 | MACHINE_START(SUN4I, "sun4i")
>> | ^~~~~~~~~~~~~
>> LD arch/arm/plat-sunxi/built-in.o
>> LD vmlinux.o
>> MODPOST vmlinux.o
>> GEN .version
>> CHK include/generated/compile.h
>> UPD include/generated/compile.h
>> CC init/version.o
>> In file included from include/linux/kernel.h:20,
>> from include/linux/cache.h:4,
>> from include/linux/time.h:7,
>> from include/linux/stat.h:60,
>> from include/linux/module.h:10,
>> from init/version.c:10:
>> include/linux/log2.h:22:1: warning: ignoring attribute ‘noreturn’
>> because it conflicts with attribute ‘const’ [-Wattributes]
>> 22 | int ____ilog2_NaN(void);
>> | ^~~
>> LD init/built-in.o
>> LD .tmp_vmlinux1
>> arm-none-linux-gnueabihf-ld: no machine record defined
>> Makefile:875: recipe for target '.tmp_vmlinux1' failed
>> make: *** [.tmp_vmlinux1] Error 1
>>
>> ---------------------------------------------------------------
>>
>> I modified the MACHINE_START macro in arch/arm/include/asm/mach/arch.h
>> and added "__attribute__((used))" so it became:
>>
>> static const struct machine_desc __mach_desc_##_type
>> __attribute__((used)) \
>>
>> And I managed to get the vmlinux image.
>>
>> -------------------------------------------------------------
>>
>>
>> arch/arm/mm/mmu.c:919:1: note: in expansion of macro ‘early_param’
>> 919 | early_param("vmalloc", early_vmalloc);
>> | ^~~~~~~~~~~
>> include/linux/init.h:241:33: warning: ‘__setup_noalign_setup’ defined
>> but not used [-Wunused-variable]
>> 241 | static struct obs_kernel_param __setup_##unique_id \
>> | ^~~~~~~~
>> include/linux/init.h:247:2: note: in expansion of macro ‘__setup_param’
>> 247 | __setup_param(str, fn, fn, 0)
>> | ^~~~~~~~~~~~~
>> arch/arm/mm/mmu.c:175:1: note: in expansion of macro ‘__setup’
>> 175 | __setup("noalign", noalign_setup);
>> | ^~~~~~~
>> include/linux/init.h:241:33: warning: ‘__setup_early_ecc’ defined but
>> not used [-Wunused-variable]
>> 241 | static struct obs_kernel_param __setup_##unique_id \
>> | ^~~~~~~~
>> include/linux/init.h:252:2: note: in expansion of macro ‘__setup_param’
>> 252 | __setup_param(str, fn, fn, 1)
>> | ^~~~~~~~~~~~~
>> arch/arm/mm/mmu.c:165:1: note: in expansion of macro ‘early_param’
>> 165 | early_param("ecc", early_ecc);
>> | ^~~~~~~~~~~
>> include/linux/init.h:241:33: warning: ‘__setup_early_nowrite’ defined
>> but not used [-Wunused-variable]
>> 241 | static struct obs_kernel_param __setup_##unique_id \
>> | ^~~~~~~~
>> include/linux/init.h:252:2: note: in expansion of macro ‘__setup_param’
>> 252 | __setup_param(str, fn, fn, 1)
>> | ^~~~~~~~~~~~~
>> arch/arm/mm/mmu.c:154:1: note: in expansion of macro ‘early_param’
>> 154 | early_param("nowb", early_nowrite);
>> | ^~~~~~~~~~~
>> include/linux/init.h:241:33: warning: ‘__setup_early_nocache’ defined
>> but not used [-Wunused-variable]
>> 241 | static struct obs_kernel_param __setup_##unique_id \
>> | ^~~~~~~~
>> include/linux/init.h:252:2: note: in expansion of macro ‘__setup_param’
>> 252 | __setup_param(str, fn, fn, 1)
>> | ^~~~~~~~~~~~~
>> arch/arm/mm/mmu.c:145:1: note: in expansion of macro ‘early_param’
>> 145 | early_param("nocache", early_nocache);
>> | ^~~~~~~~~~~
>> include/linux/init.h:241:33: warning: ‘__setup_early_cachepolicy’
>> defined but not used [-Wunused-variable]
>> 241 | static struct obs_kernel_param __setup_##unique_id \
>> | ^~~~~~~~
>> include/linux/init.h:252:2: note: in expansion of macro ‘__setup_param’
>> 252 | __setup_param(str, fn, fn, 1)
>> | ^~~~~~~~~~~~~
>> arch/arm/mm/mmu.c:136:1: note: in expansion of macro ‘early_param’
>> 136 | early_param("cachepolicy", early_cachepolicy);
>> | ^~~~~~~~~~~
>> AS arch/arm/kernel/head.o
>> LD arch/arm/kernel/built-in.o
>> AS arch/arm/mm/cache-v7.o
>> AS arch/arm/mm/tlb-v7.o
>> AS arch/arm/mm/proc-v7.o
>> LD arch/arm/mm/built-in.o
>> AS arch/arm/lib/copy_page.o
>> AS arch/arm/lib/csumpartialcopyuser.o
>> AR arch/arm/lib/lib.a
>> LD vmlinux.o
>> MODPOST vmlinux.o
>> GEN .version
>> CHK include/generated/compile.h
>> UPD include/generated/compile.h
>> CC init/version.o
>> In file included from include/linux/kernel.h:20,
>> from include/linux/cache.h:4,
>> from include/linux/time.h:7,
>> from include/linux/stat.h:60,
>> from include/linux/module.h:10,
>> from init/version.c:10:
>> include/linux/log2.h:22:1: warning: ignoring attribute ‘noreturn’
>> because it conflicts with attribute ‘const’ [-Wattributes]
>> 22 | int ____ilog2_NaN(void);
>> | ^~~
>> LD init/built-in.o
>> LD .tmp_vmlinux1
>> KSYM .tmp_kallsyms1.S
>> AS .tmp_kallsyms1.o
>> LD .tmp_vmlinux2
>> KSYM .tmp_kallsyms2.S
>> AS .tmp_kallsyms2.o
>> LD vmlinux
>> SYSMAP System.map
>> SYSMAP .tmp_System.map
>> OBJCOPY arch/arm/boot/Image
>> Kernel: arch/arm/boot/Image is ready
>> AS arch/arm/boot/compressed/head.o
>> XZKERN arch/arm/boot/compressed/piggy.xzkern
>> CC arch/arm/boot/compressed/misc.o
>> CC arch/arm/boot/compressed/decompress.o
>> CC arch/arm/boot/compressed/string.o
>> In file included from include/linux/kernel.h:20,
>> from
>> arch/arm/boot/compressed/../../../../lib/xz/xz_private.h:15,
>> from
>> arch/arm/boot/compressed/../../../../lib/decompress_unxz.c:145,
>> from arch/arm/boot/compressed/decompress.c:50:
>> include/linux/log2.h:22:1: warning: ignoring attribute ‘noreturn’
>> because it conflicts with attribute ‘const’ [-Wattributes]
>> 22 | int ____ilog2_NaN(void);
>> | ^~~
>> SHIPPED arch/arm/boot/compressed/lib1funcs.S
>> SHIPPED arch/arm/boot/compressed/ashldi3.S
>> AS arch/arm/boot/compressed/lib1funcs.o
>> AS arch/arm/boot/compressed/ashldi3.o
>> AS arch/arm/boot/compressed/piggy.xzkern.o
>> LD arch/arm/boot/compressed/vmlinux
>> OBJCOPY arch/arm/boot/zImage
>> Kernel: arch/arm/boot/zImage is ready
>> UIMAGE arch/arm/boot/uImage
>> Image Name: Linux-3.4.113-custom1
>> Created: Sun Mar 28 20:27:03 2021
>> Image Type: ARM Linux Kernel Image (uncompressed)
>> Data Size: 1869496 Bytes = 1825.68 KiB = 1.78 MiB
>> Load Address: 40008000
>> Entry Point: 40008000
>> Image arch/arm/boot/uImage is ready
>>
>>
>> -----------------------------------------------------------------------------
>>
>>
>> -- I still can't boot the kernel on the platform. I believe its
>> because there were lots of warning like above (unused const variables
>> etc) and might have removed some other code/functions OR macros?
>>
>> So please suggest what I can do for compiling working kernel-3.4 with gcc-9.
>
>
> Is it possible to switch to new kernel, like v4.4 or even newer?
As mentioned above, not possible. The mainline kernel doesn't support
the NAND chip/driver due to some binary blobs. So pretty much only
option for us is to stick with SUNXI provided 3.4.xxx kernel version.
(Mainline kernel supports Sunxi-A20 SOM from Olimex but only the eMMC
version _not_ NAND).
>
>>
>>
>> Thanks in advance,
>>
>> -- Fawad Lateef
>
>
>
> --
> With Best Regards,
> Andy Shevchenko
>
>