September 2016 - kernelnewbies@kernelnewbies.org

Extend device driver?
by Pol Eyschen Sept. 11, 2016

Sept. 11, 2016

Hi everyone, I want to implement some custom functions of my mouse (Madcatz RAT5) in Linux, e.g custom DPI-values. As this requires writing over USB to the firmware of the mouse I was thinking of writing a module to accomplish this. However I don't want to reimplement a whole mouse-driver,so I wanted to ask if there is a possibility of binding the device to 2 modules or having my module extend usbhid, so that my module would only be used to perform these custom operations while usbhid stays in charge of the whole "mouse business". Thanks Pol

3 4

Confused about rtnl routing mutex scalability
by nick Sept. 11, 2016

Sept. 11, 2016

Greetings All, I am curious as it after reading the network code for a while it seems that to me at least the rtnl mutex lock is a bottleneck. Is there any reason that we are still using a global mutex for all routing changes in the networking stack for the Linux kernel or does it actually scale only, seems to me that it is causing nothing but problems with deadlocks related to it or issues with locking timeouts on separate netdev routing tables for two different networks. Is this just me or does this lock actually cause serious issues or can do so. Regards, Nick

2 1

Getting stacktrace for userspace applications on crash(SIGSEGV)
by Daniel. Sept. 9, 2016

Sept. 9, 2016

Hi everybody, I'm debugging a library that implement some nasty protocol. This library is used by some JNI library which exports the native library to Java world. By the way I'm running on ARMv7. Well, some times, at random times, that library crashes. The problem is that I can't get stacktrace. Not from JVM's fatal errors logs, not from core dumps, not from libSegFault... I'm using "-g -rdynamic -funwind-tables -mapcs-frame" compiler options but still I can't get a stacktrace. I've tried using glibc backtrace too. What I don't tried yet: libunwind, valgrid and making kernel do the stacktrace. The cool part is that when I ran my library outside from the JVM (with native application) I do get backtraces! [Damn Java] I'm here to ask: Is it possible to make kernel print the stacktrace for some userspace application when it crashes? I saw USER_STACKTRACE_SUPPORT but can't find any help from it's Kconfig. I saw this https://kernelnewbies.org/FAQ/StackTrace and this http://processors.wiki.ti.com/index.php/Enabling_Stack_Dumping_in_Linux_Ker… but can't find "Kernel hacking -> Verbose kernel error messages" even with "Kernel hacking -> Kernel Debuggin" enabled. Any help is appreciated! Thanks !!! -- "Do or do not. There is no try" Yoda Master

3 4

Unable to boot linux-next build
by Quentin Lambert Sept. 9, 2016

Sept. 9, 2016

I have been trying to build and boot the last version available on linux-next. During the build I am being prompted with "has no CRC!" warnings for a bunch of modules. Has a result I get the following lines in the Module.symvers: [qlambert@sloth linux-next]$ grep 0x00000 Module.symvers 0x00000000 phys_base vmlinux EXPORT_SYMBOL 0x00000000 memmove vmlinux EXPORT_SYMBOL 0x00000000 __copy_user_nocache vmlinux EXPORT_SYMBOL 0x00000000 __get_user_4 vmlinux EXPORT_SYMBOL 0x00000000 __put_user_4 vmlinux EXPORT_SYMBOL 0x00000000 __memcpy vmlinux EXPORT_SYMBOL 0x00000000 __fentry__ vmlinux EXPORT_SYMBOL 0x00000000 memset vmlinux EXPORT_SYMBOL 0x00000000 __sw_hweight64 vmlinux EXPORT_SYMBOL 0x00000000 __sw_hweight32 vmlinux EXPORT_SYMBOL 0x00000000 memcpy_mcsafe_unrolled vmlinux EXPORT_SYMBOL_GPL 0x00000000 memcpy vmlinux EXPORT_SYMBOL 0x00000000 copy_user_enhanced_fast_string vmlinux EXPORT_SYMBOL 0x00000000 clear_page vmlinux EXPORT_SYMBOL 0x00000000 __put_user_2 vmlinux EXPORT_SYMBOL 0x00000000 __get_user_2 vmlinux EXPORT_SYMBOL 0x00000000 copy_page vmlinux EXPORT_SYMBOL 0x00000000 copy_user_generic_string vmlinux EXPORT_SYMBOL 0x00000000 _copy_to_user vmlinux EXPORT_SYMBOL 0x00000000 ___preempt_schedule vmlinux EXPORT_SYMBOL 0x00000000 __memmove vmlinux EXPORT_SYMBOL 0x00000000 empty_zero_page vmlinux EXPORT_SYMBOL 0x00000000 __get_user_8 vmlinux EXPORT_SYMBOL 0x00000000 __put_user_8 vmlinux EXPORT_SYMBOL 0x00000000 _copy_from_user vmlinux EXPORT_SYMBOL 0x00000000 native_load_gs_index vmlinux EXPORT_SYMBOL 0x00000000 __memset vmlinux EXPORT_SYMBOL 0x00000000 ___preempt_schedule_notrace vmlinux EXPORT_SYMBOL 0x00000000 __put_user_1 vmlinux EXPORT_SYMBOL 0x00000000 __get_user_1 vmlinux EXPORT_SYMBOL 0x00000000 copy_user_generic_unrolled vmlinux EXPORT_SYMBOL If I ignore these and go on to boot the resulting kernel. I am left with: ERROR: Unable to find root device 'UUID=<omitted>' I am then dropped to a recovery shell where the keyboard is not answering. The UUID is valid and is the same being used when I boot the HEAD of the linux tree. Prior to failing to find the root device, the kernel prints a series of message for each of the above symbol: scsi_mod: no symbol version for <foo> scsi_mod: Unknown symbol <foo> (err -22) Therefore, I suspect that the missing CRC messages are linked to the issue. I have git bisected this behavior to the patch 784d5699edd. Simply reverting this patch results in different issues. The errors I am having due to no CRC are fixed but I receive another error at boot time: failed command: WRITE LOG DMA EXT I mostly asking for help as to what to do next. Is it ok for me to send the reverting patch with an RFC tag to start the discussion ? Could someone point me toward documentation that would help me understand and fix this issue? --- arch/x86/entry/entry_32.S | 2 - arch/x86/entry/entry_64.S | 2 - arch/x86/entry/thunk_32.S | 3 -- arch/x86/entry/thunk_64.S | 3 -- arch/x86/include/asm/export.h | 4 -- arch/x86/kernel/Makefile | 4 +- arch/x86/kernel/head_32.S | 2 - arch/x86/kernel/head_64.S | 3 -- arch/x86/kernel/i386_ksyms_32.c | 47 ++++++++++++++++++++++ arch/x86/kernel/mcount_64.S | 2 - arch/x86/kernel/x8664_ksyms_64.c | 85 ++++++++++++++++++++++++++++++++++++++++ arch/x86/lib/checksum_32.S | 3 -- arch/x86/lib/clear_page_64.S | 2 - arch/x86/lib/cmpxchg8b_emu.S | 2 - arch/x86/lib/copy_page_64.S | 2 - arch/x86/lib/copy_user_64.S | 8 ---- arch/x86/lib/csum-partial_64.c | 1 - arch/x86/lib/getuser.S | 5 --- arch/x86/lib/hweight.S | 3 -- arch/x86/lib/memcpy_64.S | 4 -- arch/x86/lib/memmove_64.S | 3 -- arch/x86/lib/memset_64.S | 3 -- arch/x86/lib/putuser.S | 5 --- arch/x86/lib/strstr_32.c | 3 +- arch/x86/um/Makefile | 2 +- arch/x86/um/checksum_32.S | 2 - arch/x86/um/ksyms.c | 13 ++++++ 27 files changed, 150 insertions(+), 68 deletions(-) delete mode 100644 arch/x86/include/asm/export.h create mode 100644 arch/x86/kernel/i386_ksyms_32.c create mode 100644 arch/x86/kernel/x8664_ksyms_64.c create mode 100644 arch/x86/um/ksyms.c diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index 21b352a11b49..b75a8bcd2d23 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -44,7 +44,6 @@ #include <asm/alternative-asm.h> #include <asm/asm.h> #include <asm/smap.h> -#include <asm/export.h> .section .entry.text, "ax" @@ -992,7 +991,6 @@ trace: jmp ftrace_stub END(mcount) #endif /* CONFIG_DYNAMIC_FTRACE */ -EXPORT_SYMBOL(mcount) #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index b9ca6b34b6c5..c0373d667674 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -35,7 +35,6 @@ #include <asm/asm.h> #include <asm/smap.h> #include <asm/pgtable_types.h> -#include <asm/export.h> #include <linux/err.h> /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */ @@ -832,7 +831,6 @@ ENTRY(native_load_gs_index) popfq ret END(native_load_gs_index) -EXPORT_SYMBOL(native_load_gs_index) _ASM_EXTABLE(.Lgs_change, bad_gs) .section .fixup, "ax" diff --git a/arch/x86/entry/thunk_32.S b/arch/x86/entry/thunk_32.S index fee6bc79b987..e5a17114a8c4 100644 --- a/arch/x86/entry/thunk_32.S +++ b/arch/x86/entry/thunk_32.S @@ -6,7 +6,6 @@ */ #include <linux/linkage.h> #include <asm/asm.h> - #include <asm/export.h> /* put return address in eax (arg1) */ .macro THUNK name, func, put_ret_addr_in_eax=0 @@ -37,7 +36,5 @@ #ifdef CONFIG_PREEMPT THUNK ___preempt_schedule, preempt_schedule THUNK ___preempt_schedule_notrace, preempt_schedule_notrace - EXPORT_SYMBOL(___preempt_schedule) - EXPORT_SYMBOL(___preempt_schedule_notrace) #endif diff --git a/arch/x86/entry/thunk_64.S b/arch/x86/entry/thunk_64.S index be36bf4e0957..627ecbcb2e62 100644 --- a/arch/x86/entry/thunk_64.S +++ b/arch/x86/entry/thunk_64.S @@ -8,7 +8,6 @@ #include <linux/linkage.h> #include "calling.h" #include <asm/asm.h> -#include <asm/export.h> /* rdi: arg1 ... normal C conventions. rax is saved/restored. */ .macro THUNK name, func, put_ret_addr_in_rdi=0 @@ -50,8 +49,6 @@ #ifdef CONFIG_PREEMPT THUNK ___preempt_schedule, preempt_schedule THUNK ___preempt_schedule_notrace, preempt_schedule_notrace - EXPORT_SYMBOL(___preempt_schedule) - EXPORT_SYMBOL(___preempt_schedule_notrace) #endif #if defined(CONFIG_TRACE_IRQFLAGS) \ diff --git a/arch/x86/include/asm/export.h b/arch/x86/include/asm/export.h deleted file mode 100644 index 138de56b13eb..000000000000 --- a/arch/x86/include/asm/export.h +++ /dev/null @@ -1,4 +0,0 @@ -#ifdef CONFIG_64BIT -#define KSYM_ALIGN 16 -#endif -#include <asm-generic/export.h> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 92fd50c77875..4f656fe156fd 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -46,7 +46,9 @@ obj-$(CONFIG_MODIFY_LDT_SYSCALL) += ldt.o obj-y += setup.o x86_init.o i8259.o irqinit.o jump_label.o obj-$(CONFIG_IRQ_WORK) += irq_work.o obj-y += probe_roms.o -obj-$(CONFIG_X86_64) += sys_x86_64.o mcount_64.o +obj-$(CONFIG_X86_32) += i386_ksyms_32.o +obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o +obj-$(CONFIG_X86_64) += mcount_64.o obj-$(CONFIG_X86_ESPFIX64) += espfix_64.o obj-$(CONFIG_SYSFS) += ksysfs.o obj-y += bootflag.o e820.o diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index b6b2f0264af3..5f401262f12d 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -23,7 +23,6 @@ #include <asm/percpu.h> #include <asm/nops.h> #include <asm/bootparam.h> -#include <asm/export.h> /* Physical address */ #define pa(X) ((X) - __PAGE_OFFSET) @@ -674,7 +673,6 @@ ENTRY(empty_zero_page) .fill 4096,1,0 ENTRY(swapper_pg_dir) .fill 1024,4,0 -EXPORT_SYMBOL(empty_zero_page) /* * This starts the data section. diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index b4421cc191b0..c98a559c346e 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -21,7 +21,6 @@ #include <asm/percpu.h> #include <asm/nops.h> #include "../entry/calling.h" -#include <asm/export.h> #ifdef CONFIG_PARAVIRT #include <asm/asm-offsets.h> @@ -487,12 +486,10 @@ early_gdt_descr_base: ENTRY(phys_base) /* This must match the first entry in level2_kernel_pgt */ .quad 0x0000000000000000 -EXPORT_SYMBOL(phys_base) #include "../../x86/xen/xen-head.S" __PAGE_ALIGNED_BSS NEXT_PAGE(empty_zero_page) .skip PAGE_SIZE -EXPORT_SYMBOL(empty_zero_page) diff --git a/arch/x86/kernel/i386_ksyms_32.c b/arch/x86/kernel/i386_ksyms_32.c new file mode 100644 index 000000000000..1f9b878ef5ef --- /dev/null +++ b/arch/x86/kernel/i386_ksyms_32.c @@ -0,0 +1,47 @@ +#include <linux/export.h> +#include <linux/spinlock_types.h> + +#include <asm/checksum.h> +#include <asm/pgtable.h> +#include <asm/desc.h> +#include <asm/ftrace.h> + +#ifdef CONFIG_FUNCTION_TRACER +/* mcount is defined in assembly */ +EXPORT_SYMBOL(mcount); +#endif + +/* + * Note, this is a prototype to get at the symbol for + * the export, but dont use it from C code, it is used + * by assembly code and is not using C calling convention! + */ +#ifndef CONFIG_X86_CMPXCHG64 +extern void cmpxchg8b_emu(void); +EXPORT_SYMBOL(cmpxchg8b_emu); +#endif + +/* Networking helper routines. */ +EXPORT_SYMBOL(csum_partial_copy_generic); + +EXPORT_SYMBOL(__get_user_1); +EXPORT_SYMBOL(__get_user_2); +EXPORT_SYMBOL(__get_user_4); +EXPORT_SYMBOL(__get_user_8); + +EXPORT_SYMBOL(__put_user_1); +EXPORT_SYMBOL(__put_user_2); +EXPORT_SYMBOL(__put_user_4); +EXPORT_SYMBOL(__put_user_8); + +EXPORT_SYMBOL(strstr); + +EXPORT_SYMBOL(csum_partial); +EXPORT_SYMBOL(empty_zero_page); + +#ifdef CONFIG_PREEMPT +EXPORT_SYMBOL(___preempt_schedule); +EXPORT_SYMBOL(___preempt_schedule_notrace); +#endif + +EXPORT_SYMBOL(__sw_hweight32); diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S index efe73aacf966..61924222a9e1 100644 --- a/arch/x86/kernel/mcount_64.S +++ b/arch/x86/kernel/mcount_64.S @@ -7,7 +7,6 @@ #include <linux/linkage.h> #include <asm/ptrace.h> #include <asm/ftrace.h> -#include <asm/export.h> .code64 @@ -295,7 +294,6 @@ trace: jmp fgraph_trace END(function_hook) #endif /* CONFIG_DYNAMIC_FTRACE */ -EXPORT_SYMBOL(function_hook) #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c new file mode 100644 index 000000000000..b2cee3d19477 --- /dev/null +++ b/arch/x86/kernel/x8664_ksyms_64.c @@ -0,0 +1,85 @@ +/* Exports for assembly files. + All C exports should go in the respective C files. */ + +#include <linux/export.h> +#include <linux/spinlock_types.h> +#include <linux/smp.h> + +#include <net/checksum.h> + +#include <asm/processor.h> +#include <asm/pgtable.h> +#include <asm/uaccess.h> +#include <asm/desc.h> +#include <asm/ftrace.h> + +#ifdef CONFIG_FUNCTION_TRACER +/* mcount and __fentry__ are defined in assembly */ +#ifdef CC_USING_FENTRY +EXPORT_SYMBOL(__fentry__); +#else +EXPORT_SYMBOL(mcount); +#endif +#endif + +EXPORT_SYMBOL(__get_user_1); +EXPORT_SYMBOL(__get_user_2); +EXPORT_SYMBOL(__get_user_4); +EXPORT_SYMBOL(__get_user_8); +EXPORT_SYMBOL(__put_user_1); +EXPORT_SYMBOL(__put_user_2); +EXPORT_SYMBOL(__put_user_4); +EXPORT_SYMBOL(__put_user_8); + +EXPORT_SYMBOL(copy_user_generic_string); +EXPORT_SYMBOL(copy_user_generic_unrolled); +EXPORT_SYMBOL(copy_user_enhanced_fast_string); +EXPORT_SYMBOL(__copy_user_nocache); +EXPORT_SYMBOL(_copy_from_user); +EXPORT_SYMBOL(_copy_to_user); + +EXPORT_SYMBOL_GPL(memcpy_mcsafe_unrolled); + +EXPORT_SYMBOL(copy_page); +EXPORT_SYMBOL(clear_page); + +EXPORT_SYMBOL(csum_partial); + +EXPORT_SYMBOL(__sw_hweight32); +EXPORT_SYMBOL(__sw_hweight64); + +/* + * Export string functions. We normally rely on gcc builtin for most of these, + * but gcc sometimes decides not to inline them. + */ +#undef memcpy +#undef memset +#undef memmove + +extern void *__memset(void *, int, __kernel_size_t); +extern void *__memcpy(void *, const void *, __kernel_size_t); +extern void *__memmove(void *, const void *, __kernel_size_t); +extern void *memset(void *, int, __kernel_size_t); +extern void *memcpy(void *, const void *, __kernel_size_t); +extern void *memmove(void *, const void *, __kernel_size_t); + +EXPORT_SYMBOL(__memset); +EXPORT_SYMBOL(__memcpy); +EXPORT_SYMBOL(__memmove); + +EXPORT_SYMBOL(memset); +EXPORT_SYMBOL(memcpy); +EXPORT_SYMBOL(memmove); + +#ifndef CONFIG_DEBUG_VIRTUAL +EXPORT_SYMBOL(phys_base); +#endif +EXPORT_SYMBOL(empty_zero_page); +#ifndef CONFIG_PARAVIRT +EXPORT_SYMBOL(native_load_gs_index); +#endif + +#ifdef CONFIG_PREEMPT +EXPORT_SYMBOL(___preempt_schedule); +EXPORT_SYMBOL(___preempt_schedule_notrace); +#endif diff --git a/arch/x86/lib/checksum_32.S b/arch/x86/lib/checksum_32.S index 4d34bb548b41..c1e623209853 100644 --- a/arch/x86/lib/checksum_32.S +++ b/arch/x86/lib/checksum_32.S @@ -28,7 +28,6 @@ #include <linux/linkage.h> #include <asm/errno.h> #include <asm/asm.h> -#include <asm/export.h> /* * computes a partial checksum, e.g. for TCP/UDP fragments @@ -252,7 +251,6 @@ ENTRY(csum_partial) ENDPROC(csum_partial) #endif -EXPORT_SYMBOL(csum_partial) /* unsigned int csum_partial_copy_generic (const char *src, char *dst, @@ -492,4 +490,3 @@ ENDPROC(csum_partial_copy_generic) #undef ROUND1 #endif -EXPORT_SYMBOL(csum_partial_copy_generic) diff --git a/arch/x86/lib/clear_page_64.S b/arch/x86/lib/clear_page_64.S index 5e2af3a88cf5..65be7cfaf947 100644 --- a/arch/x86/lib/clear_page_64.S +++ b/arch/x86/lib/clear_page_64.S @@ -1,7 +1,6 @@ #include <linux/linkage.h> #include <asm/cpufeatures.h> #include <asm/alternative-asm.h> -#include <asm/export.h> /* * Most CPUs support enhanced REP MOVSB/STOSB instructions. It is @@ -24,7 +23,6 @@ ENTRY(clear_page) rep stosq ret ENDPROC(clear_page) -EXPORT_SYMBOL(clear_page) ENTRY(clear_page_orig) diff --git a/arch/x86/lib/cmpxchg8b_emu.S b/arch/x86/lib/cmpxchg8b_emu.S index 03a186fc06ea..ad5349778490 100644 --- a/arch/x86/lib/cmpxchg8b_emu.S +++ b/arch/x86/lib/cmpxchg8b_emu.S @@ -7,7 +7,6 @@ */ #include <linux/linkage.h> -#include <asm/export.h> .text @@ -49,4 +48,3 @@ ENTRY(cmpxchg8b_emu) ret ENDPROC(cmpxchg8b_emu) -EXPORT_SYMBOL(cmpxchg8b_emu) diff --git a/arch/x86/lib/copy_page_64.S b/arch/x86/lib/copy_page_64.S index e8508156c99d..24ef1c2104d4 100644 --- a/arch/x86/lib/copy_page_64.S +++ b/arch/x86/lib/copy_page_64.S @@ -3,7 +3,6 @@ #include <linux/linkage.h> #include <asm/cpufeatures.h> #include <asm/alternative-asm.h> -#include <asm/export.h> /* * Some CPUs run faster using the string copy instructions (sane microcode). @@ -18,7 +17,6 @@ ENTRY(copy_page) rep movsq ret ENDPROC(copy_page) -EXPORT_SYMBOL(copy_page) ENTRY(copy_page_regs) subq $2*8, %rsp diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S index d376e4b48f88..bf603ebbfd8e 100644 --- a/arch/x86/lib/copy_user_64.S +++ b/arch/x86/lib/copy_user_64.S @@ -14,7 +14,6 @@ #include <asm/alternative-asm.h> #include <asm/asm.h> #include <asm/smap.h> -#include <asm/export.h> /* Standard copy_to_user with segment limit checking */ ENTRY(_copy_to_user) @@ -30,7 +29,6 @@ ENTRY(_copy_to_user) "jmp copy_user_enhanced_fast_string", \ X86_FEATURE_ERMS ENDPROC(_copy_to_user) -EXPORT_SYMBOL(_copy_to_user) /* Standard copy_from_user with segment limit checking */ ENTRY(_copy_from_user) @@ -46,8 +44,6 @@ ENTRY(_copy_from_user) "jmp copy_user_enhanced_fast_string", \ X86_FEATURE_ERMS ENDPROC(_copy_from_user) -EXPORT_SYMBOL(_copy_from_user) - .section .fixup,"ax" /* must zero dest */ @@ -159,7 +155,6 @@ ENTRY(copy_user_generic_unrolled) _ASM_EXTABLE(21b,50b) _ASM_EXTABLE(22b,50b) ENDPROC(copy_user_generic_unrolled) -EXPORT_SYMBOL(copy_user_generic_unrolled) /* Some CPUs run faster using the string copy instructions. * This is also a lot simpler. Use them when possible. @@ -205,7 +200,6 @@ ENTRY(copy_user_generic_string) _ASM_EXTABLE(1b,11b) _ASM_EXTABLE(3b,12b) ENDPROC(copy_user_generic_string) -EXPORT_SYMBOL(copy_user_generic_string) /* * Some CPUs are adding enhanced REP MOVSB/STOSB instructions. @@ -235,7 +229,6 @@ ENTRY(copy_user_enhanced_fast_string) _ASM_EXTABLE(1b,12b) ENDPROC(copy_user_enhanced_fast_string) -EXPORT_SYMBOL(copy_user_enhanced_fast_string) /* * copy_user_nocache - Uncached memory copy with exception handling @@ -386,4 +379,3 @@ ENTRY(__copy_user_nocache) _ASM_EXTABLE(40b,.L_fixup_1b_copy) _ASM_EXTABLE(41b,.L_fixup_1b_copy) ENDPROC(__copy_user_nocache) -EXPORT_SYMBOL(__copy_user_nocache) diff --git a/arch/x86/lib/csum-partial_64.c b/arch/x86/lib/csum-partial_64.c index 378e5d5bf9b1..9a7fe6a70491 100644 --- a/arch/x86/lib/csum-partial_64.c +++ b/arch/x86/lib/csum-partial_64.c @@ -135,7 +135,6 @@ __wsum csum_partial(const void *buff, int len, __wsum sum) return (__force __wsum)add32_with_carry(do_csum(buff, len), (__force u32)sum); } -EXPORT_SYMBOL(csum_partial); /* * this routine is used for miscellaneous IP-like checksums, mainly diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S index 37b62d412148..0ef5128c2de8 100644 --- a/arch/x86/lib/getuser.S +++ b/arch/x86/lib/getuser.S @@ -32,7 +32,6 @@ #include <asm/thread_info.h> #include <asm/asm.h> #include <asm/smap.h> -#include <asm/export.h> .text ENTRY(__get_user_1) @@ -45,7 +44,6 @@ ENTRY(__get_user_1) ASM_CLAC ret ENDPROC(__get_user_1) -EXPORT_SYMBOL(__get_user_1) ENTRY(__get_user_2) add $1,%_ASM_AX @@ -59,7 +57,6 @@ ENTRY(__get_user_2) ASM_CLAC ret ENDPROC(__get_user_2) -EXPORT_SYMBOL(__get_user_2) ENTRY(__get_user_4) add $3,%_ASM_AX @@ -73,7 +70,6 @@ ENTRY(__get_user_4) ASM_CLAC ret ENDPROC(__get_user_4) -EXPORT_SYMBOL(__get_user_4) ENTRY(__get_user_8) #ifdef CONFIG_X86_64 @@ -101,7 +97,6 @@ ENTRY(__get_user_8) ret #endif ENDPROC(__get_user_8) -EXPORT_SYMBOL(__get_user_8) bad_get_user: diff --git a/arch/x86/lib/hweight.S b/arch/x86/lib/hweight.S index 23d893cbc200..8a602a1e404a 100644 --- a/arch/x86/lib/hweight.S +++ b/arch/x86/lib/hweight.S @@ -1,5 +1,4 @@ #include <linux/linkage.h> -#include <asm/export.h> #include <asm/asm.h> @@ -33,7 +32,6 @@ ENTRY(__sw_hweight32) __ASM_SIZE(pop,) %__ASM_REG(dx) ret ENDPROC(__sw_hweight32) -EXPORT_SYMBOL(__sw_hweight32) ENTRY(__sw_hweight64) #ifdef CONFIG_X86_64 @@ -79,4 +77,3 @@ ENTRY(__sw_hweight64) ret #endif ENDPROC(__sw_hweight64) -EXPORT_SYMBOL(__sw_hweight64) diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S index 779782f58324..49e6ebac7e73 100644 --- a/arch/x86/lib/memcpy_64.S +++ b/arch/x86/lib/memcpy_64.S @@ -4,7 +4,6 @@ #include <asm/errno.h> #include <asm/cpufeatures.h> #include <asm/alternative-asm.h> -#include <asm/export.h> /* * We build a jump to memcpy_orig by default which gets NOPped out on @@ -41,8 +40,6 @@ ENTRY(memcpy) ret ENDPROC(memcpy) ENDPROC(__memcpy) -EXPORT_SYMBOL(memcpy) -EXPORT_SYMBOL(__memcpy) /* * memcpy_erms() - enhanced fast string memcpy. This is faster and @@ -277,7 +274,6 @@ ENTRY(memcpy_mcsafe_unrolled) xorq %rax, %rax ret ENDPROC(memcpy_mcsafe_unrolled) -EXPORT_SYMBOL_GPL(memcpy_mcsafe_unrolled) .section .fixup, "ax" /* Return -EFAULT for any failure */ diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S index 15de86cd15b0..90ce01bee00c 100644 --- a/arch/x86/lib/memmove_64.S +++ b/arch/x86/lib/memmove_64.S @@ -8,7 +8,6 @@ #include <linux/linkage.h> #include <asm/cpufeatures.h> #include <asm/alternative-asm.h> -#include <asm/export.h> #undef memmove @@ -208,5 +207,3 @@ ENTRY(__memmove) retq ENDPROC(__memmove) ENDPROC(memmove) -EXPORT_SYMBOL(__memmove) -EXPORT_SYMBOL(memmove) diff --git a/arch/x86/lib/memset_64.S b/arch/x86/lib/memset_64.S index 55b95db30a61..e1229ecd2a82 100644 --- a/arch/x86/lib/memset_64.S +++ b/arch/x86/lib/memset_64.S @@ -3,7 +3,6 @@ #include <linux/linkage.h> #include <asm/cpufeatures.h> #include <asm/alternative-asm.h> -#include <asm/export.h> .weak memset @@ -44,8 +43,6 @@ ENTRY(__memset) ret ENDPROC(memset) ENDPROC(__memset) -EXPORT_SYMBOL(memset) -EXPORT_SYMBOL(__memset) /* * ISO C memset - set a memory block to a byte value. This function uses diff --git a/arch/x86/lib/putuser.S b/arch/x86/lib/putuser.S index cd5d716d2897..c891ece81e5b 100644 --- a/arch/x86/lib/putuser.S +++ b/arch/x86/lib/putuser.S @@ -15,7 +15,6 @@ #include <asm/errno.h> #include <asm/asm.h> #include <asm/smap.h> -#include <asm/export.h> /* @@ -44,7 +43,6 @@ ENTRY(__put_user_1) xor %eax,%eax EXIT ENDPROC(__put_user_1) -EXPORT_SYMBOL(__put_user_1) ENTRY(__put_user_2) ENTER @@ -57,7 +55,6 @@ ENTRY(__put_user_2) xor %eax,%eax EXIT ENDPROC(__put_user_2) -EXPORT_SYMBOL(__put_user_2) ENTRY(__put_user_4) ENTER @@ -70,7 +67,6 @@ ENTRY(__put_user_4) xor %eax,%eax EXIT ENDPROC(__put_user_4) -EXPORT_SYMBOL(__put_user_4) ENTRY(__put_user_8) ENTER @@ -86,7 +82,6 @@ ENTRY(__put_user_8) xor %eax,%eax EXIT ENDPROC(__put_user_8) -EXPORT_SYMBOL(__put_user_8) bad_put_user: movl $-EFAULT,%eax diff --git a/arch/x86/lib/strstr_32.c b/arch/x86/lib/strstr_32.c index a03b1c750bfe..8e2d55f754bf 100644 --- a/arch/x86/lib/strstr_32.c +++ b/arch/x86/lib/strstr_32.c @@ -1,5 +1,4 @@ #include <linux/string.h> -#include <linux/export.h> char *strstr(const char *cs, const char *ct) { @@ -29,4 +28,4 @@ __asm__ __volatile__( : "dx", "di"); return __res; } -EXPORT_SYMBOL(strstr); + diff --git a/arch/x86/um/Makefile b/arch/x86/um/Makefile index e7e7055a8658..3ee2bb6b440b 100644 --- a/arch/x86/um/Makefile +++ b/arch/x86/um/Makefile @@ -8,7 +8,7 @@ else BITS := 64 endif -obj-y = bug.o bugs_$(BITS).o delay.o fault.o ldt.o \ +obj-y = bug.o bugs_$(BITS).o delay.o fault.o ksyms.o ldt.o \ ptrace_$(BITS).o ptrace_user.o setjmp_$(BITS).o signal.o \ stub_$(BITS).o stub_segv.o \ sys_call_table_$(BITS).o sysrq_$(BITS).o tls_$(BITS).o \ diff --git a/arch/x86/um/checksum_32.S b/arch/x86/um/checksum_32.S index b9933eb9274a..fa4b8b9841ff 100644 --- a/arch/x86/um/checksum_32.S +++ b/arch/x86/um/checksum_32.S @@ -27,7 +27,6 @@ #include <asm/errno.h> #include <asm/asm.h> -#include <asm/export.h> /* * computes a partial checksum, e.g. for TCP/UDP fragments @@ -215,4 +214,3 @@ csum_partial: ret #endif - EXPORT_SYMBOL(csum_partial) diff --git a/arch/x86/um/ksyms.c b/arch/x86/um/ksyms.c new file mode 100644 index 000000000000..2e8f43ec6214 --- /dev/null +++ b/arch/x86/um/ksyms.c @@ -0,0 +1,13 @@ +#include <linux/module.h> +#include <asm/string.h> +#include <asm/checksum.h> + +#ifndef CONFIG_X86_32 +/*XXX: we need them because they would be exported by x86_64 */ +#if (__GNUC__ == 4 && __GNUC_MINOR__ >= 3) || __GNUC__ > 4 +EXPORT_SYMBOL(memcpy); +#else +EXPORT_SYMBOL(__memcpy); +#endif +#endif +EXPORT_SYMBOL(csum_partial); -- 2.9.3

2 3

Creating sysfs brightness for every led channels
by Raul Piper Sept. 8, 2016

Sept. 8, 2016

Hi, I am trying to send the brightness value ( for 5 channels) by echo "val1val2val3val4val5" > brightness , But seems like even if I change the brightness type to enum or int in my driver ,I will never be able to send the brightness string because led class defines the brightness value as enum. extern void led_set_brightness(struct led_classdev *led_cdev, enum led_brightness brightness); Only possible way I am finding is to create attributes for each channel like brightness,default trigger,max_brightness and any user defined attributes, but i am not getting how to do this. Can some on please comment or post the link to the example driver. Do i have to call led_class_register for every channel and I have to define every channel in the device tree? Thanks in advance ! Regards, Rp

2 3

How to find closest tag when using git-bisect?
by Louie Lu Sept. 8, 2016

Sept. 8, 2016

Hi everyone, I'm trying to git-bisect for debugging, but how can I find the tag I need? for example, I'm find the file change at maybe commit fc2bd799c7c79c84a59da6f9221370bc6f38c503, how to find the closest tag for this commit? and a anther question is, is every bisect need to recopmile all kernel code by `make`? or just need to build the thing I need? thanks. Louie.

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[Kernel Build] Initrd not getting build out of source dir
by Vipul Jain Sept. 8, 2016

Sept. 8, 2016

Hi Kernel Alias, I downloaded latest kernel source from kernel.org and tried to build it at a directory outside source by giving O=<path option> but I noticed that initrd image is not getting build but if I execute make inside source things are fine. [Build Kernel/Modules etc inside source] ~/linux-stable/> make ~/linux-stable/> make install ~/linux-stable/> make install_modules ~/linux-stable/> su -c "reboot -f" everything works out fine and system gives me selection to boot from newly build kernel and system boots up without issues. But if I build as below I see system OOPS because no file system found for mount. Would like to know why? [Build outside] ~/linux-stable/> make O=~/linux-build/ ~/linux-stable/> cd ../linux-build/ ~/linux-stable/> make install ~/linux-stable/> make install_modules ~/linux-stable/> su -c "reboot -f" Regards, Vipul.

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Fwd: Kernel information about organization of DRAM
by Babis Chalios Sept. 7, 2016

Sept. 7, 2016

Hello, I m trying to find out whether the kernel represents somehow the organization of the main memory in finer granularity than memory nodes, e.g. DIMMS, DRAM devices, etc. I understand that information about physical memory in architectures like ARM64 might be provided as part of the DTS and overriden by the bootloader but I couldn't find if/how that level of information is kept in the kernel after booting. Also, I took a look in the code related to memory hotplugging, assuming that there would be some information there regarding whether a DIMM is online or offline, but this didn't help either. Any directions on where to look? Babis

1 0

Re: Request Chinese mail list and FrontPage
by Andrey Utkin Sept. 7, 2016

Sept. 7, 2016

On Mon, Sep 05, 2016 at 01:40:23PM -0400, swalow swalow wrote: > Sorry for being a newb and speaking out but maybe the reason is that this > mail list is in English and they don't feel comfortable answering/asking in > it? There might be other reasons that my Western educated brain cannot > grasp. If it's not too much work, why not give them a chance? Worst case > they will come back here and be forced to ask the question in English. Best > case more people will be involved in the conversation. Replying in public. My vision is that if some nice people of Chinese origination AND qualified as experienced kernel developers would have time and habit to reply newbie questions on kernelnewbies mailing list, they would often reply also to questions posted in English, because - to succeed as kernel dev you must have good English, so good kernel devs all know English well, and - it would be unfair to answer only to your compatriots when a lot of newbies of different nations want help, too. And what I see happening is that no people with Chinese names are answering the questions here. Most of answers come from Greg Kroah-Hartman, who doesn't speak Chinese I guess. However, I'm watching this list just for two weeks, so my conclusion may be wrong.

8 7

initrd in embedded systems
by Madhu K Sept. 7, 2016

Sept. 7, 2016

Hi All, I have one doubt, does all embedded system with Linux as operating system have initrd? Thanks & regards, Madhu

2 1