[PATCH] um: add 2 missing libs to fix various build errors

Sat Apr 10 06:28:41 BST 2021

On 10/04/2021 05:13, Randy Dunlap wrote:
> On 4/4/21 11:20 AM, Randy Dunlap wrote:
>> Fix many build errors (at least 18 build error reports) for uml on i386
>> by adding 2 more library object files. All missing symbols are
>> either cmpxchg8b_emu or atomic*386.
>>
>> Here are a few examples of the build errors that are eliminated:
>>
>>     /usr/bin/ld: core.c:(.text+0xd83): undefined reference to `cmpxchg8b_emu'
>>     /usr/bin/ld: core.c:(.text+0x2bb2): undefined reference to `atomic64_add_386'
>>     /usr/bin/ld: core.c:(.text+0x2c5d): undefined reference to `atomic64_xchg_386'
>>     syscall.c:(.text+0x2f49): undefined reference to `atomic64_set_386'
>>     /usr/bin/ld: syscall.c:(.text+0x2f54): undefined reference to `atomic64_set_386'
>>     syscall.c:(.text+0x33a4): undefined reference to `atomic64_inc_386'
>>     /usr/bin/ld: syscall.c:(.text+0x33ac): undefined reference to `atomic64_inc_386'
>>     /usr/bin/ld: net/ipv4/inet_timewait_sock.o: in function `inet_twsk_alloc':
>>     inet_timewait_sock.c:(.text+0x3d1): undefined reference to `atomic64_read_386'
>>     /usr/bin/ld: inet_timewait_sock.c:(.text+0x3dd): undefined reference to `atomic64_set_386'
>>     /usr/bin/ld: net/ipv4/inet_connection_sock.o: in function `inet_csk_clone_lock':
>>     inet_connection_sock.c:(.text+0x1d74): undefined reference to `atomic64_read_386'
>>     /usr/bin/ld: inet_connection_sock.c:(.text+0x1d80): undefined reference to `atomic64_set_386'
>>     /usr/bin/ld: net/ipv4/tcp_input.o: in function `inet_reqsk_alloc':
>>     tcp_input.c:(.text+0xa345): undefined reference to `atomic64_set_386'
>>     /usr/bin/ld: net/mac80211/wpa.o: in function `ieee80211_crypto_tkip_encrypt':
>>     wpa.c:(.text+0x739): undefined reference to `atomic64_inc_return_386'
>>
>> Signed-off-by: Randy Dunlap <rdunlap at infradead.org>
>> Reported-by: kernel test robot <lkp at intel.com>
>> Cc: Brendan Jackman <jackmanb at google.com>
>> Cc: Alexei Starovoitov <ast at kernel.org>
>> Cc: kbuild-all at lists.01.org
>> Cc: Jeff Dike <jdike at addtoit.com>
>> Cc: Richard Weinberger <richard at nod.at>
>> Cc: Anton Ivanov <anton.ivanov at cambridgegreys.com>
>> Cc: linux-um at lists.infradead.org
>> Cc: Johannes Berg <johannes at sipsolutions.net>
>> Cc: Johannes Berg <johannes.berg at intel.com>
>> ---
>> My UML on i386 build environment is br0ken so this is not tested other
>> than to see that the .o files are built as expected.
>> If someone can test/verify it, please respond. Thanks.
> 
> Hi,
> Instead of trying to build this on x86_64, I powered up my 32-bit x86
> laptop and verified that this patch fixes the build errors of
> undefined references to cmpxchg8b_emu() and atomic64_*_386() functions.
> 
> There are still some build errors in 2 object files:
> 
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x8): undefined reference to `X86_FEATURE_XMM2'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x15): undefined reference to `X86_FEATURE_XMM2'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x22): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x2f): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x3c): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x49): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x56): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: kernel/irq/generic-chip.o:(.altinstructions+0x63): more undefined references to `X86_FEATURE_XMM' follow
> 
> and
> 
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x8): undefined reference to `X86_FEATURE_XMM2'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x15): undefined reference to `X86_FEATURE_XMM2'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x22): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x2f): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x3c): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x49): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x56): undefined reference to `X86_FEATURE_XMM'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x63): undefined reference to `X86_FEATURE_XMM2'
> /usr/lib/gcc/i586-suse-linux/10/../../../../i586-suse-linux/bin/ld: drivers/fpga/altera-pr-ip-core.o:(.altinstructions+0x70): undefined reference to `X86_FEATURE_XMM2'
> 
> I don't know what to do about these or what is causing them (other than
> "alternatives").

I have a patch in the queue which should fix these - it "steals" the 
bug/feature definitions from the x86 tree.

A

> 
> 
> 
>>   arch/x86/um/Makefile |    1 +
>>   1 file changed, 1 insertion(+)
>>
>> --- lnx-512-rc5.orig/arch/x86/um/Makefile
>> +++ lnx-512-rc5/arch/x86/um/Makefile
>> @@ -21,6 +21,7 @@ obj-y += checksum_32.o syscalls_32.o
>>   obj-$(CONFIG_ELF_CORE) += elfcore.o
>>   
>>   subarch-y = ../lib/string_32.o ../lib/atomic64_32.o ../lib/atomic64_cx8_32.o
>> +subarch-y += ../lib/cmpxchg8b_emu.o ../lib/atomic64_386_32.o
>>   subarch-y += ../kernel/sys_ia32.o
>>   
>>   else
>>
> 
> 

-- 
Anton R. Ivanov
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