kernel/linux.git/arch/um/Makefile, branch linux-4.16.y

um: make sure to have generated headers for target

2017-11-27T21:19:51+00:00

Signed-off-by: Al Viro

um: link vmlinux with -no-pie

2017-09-13T20:34:30+00:00

Debian's gcc defaults to pie. The global Makefile already defines the -fno-pie option. Link UML dynamic kernel image also with -no-pie to fix the build. Signed-off-by: Thomas Meyer Signed-off-by: Richard Weinberger

um: Avoid longjmp/setjmp symbol clashes with libpthread.a

2017-07-05T21:30:50+00:00

Building a statically linked UML kernel on a Centos 6.9 host resulted in the following linking failure (GCC 4.4, glibc-2.12): /usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../lib64/libpthread.a(libpthread.o): In function `siglongjmp': (.text+0x8490): multiple definition of `longjmp' arch/x86/um/built-in.o:/local/users/fainelli/openwrt/trunk/build_dir/target-x86_64_musl/linux-uml/linux-4.4.69/arch/x86/um/setjmp_64.S:44: first defined here /usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../lib64/libpthread.a(libpthread.o): In function `sem_open': (.text+0x77cd): warning: the use of `mktemp' is dangerous, better use `mkstemp' collect2: ld returned 1 exit status make[4]: *** [vmlinux] Error 1 Adopt a solution similar to the one done for vmap where we define longjmp/setjmp to be kernel_longjmp/setjmp. In the process, make sure we do rename the functions in arch/x86/um/setjmp_*.S accordingly. Fixes: a7df4716d195 ("um: link with -lpthread") Signed-off-by: Florian Fainelli Signed-off-by: Richard Weinberger

Kbuild: arch: look for generated headers in obtree

2016-07-18T19:31:35+00:00

There are very few files that need add an -I$(obj) gcc for the preprocessor or the assembler. For C files, we add always these for both the objtree and srctree, but for the other ones we require the Makefile to add them, and Kbuild then adds it for both trees. As a preparation for changing the meaning of the -I$(obj) directive to only refer to the srctree, this changes the two instances in arch/x86 to use an explictit $(objtree) prefix where needed, otherwise we won't find the headers any more, as reported by the kbuild 0day builder. arch/x86/realmode/rm/realmode.lds.S:75:20: fatal error: pasyms.h: No such file or directory Signed-off-by: Arnd Bergmann Signed-off-by: Michal Marek

arch: um: fix error when linking vmlinux.

2015-12-08T21:25:13+00:00

On gcc Ubuntu 4.8.4-2ubuntu1~14.04, linking vmlinux fails with: arch/um/os-Linux/built-in.o: In function `os_timer_create': /android/kernel/android/arch/um/os-Linux/time.c:51: undefined reference to `timer_create' arch/um/os-Linux/built-in.o: In function `os_timer_set_interval': /android/kernel/android/arch/um/os-Linux/time.c:84: undefined reference to `timer_settime' arch/um/os-Linux/built-in.o: In function `os_timer_remain': /android/kernel/android/arch/um/os-Linux/time.c:109: undefined reference to `timer_gettime' arch/um/os-Linux/built-in.o: In function `os_timer_one_shot': /android/kernel/android/arch/um/os-Linux/time.c:132: undefined reference to `timer_settime' arch/um/os-Linux/built-in.o: In function `os_timer_disable': /android/kernel/android/arch/um/os-Linux/time.c:145: undefined reference to `timer_settime' This is because -lrt appears in the generated link commandline after arch/um/os-Linux/built-in.o. Fix this by removing -lrt from arch/um/Makefile and adding it to the UM-specific section of scripts/link-vmlinux.sh. Signed-off-by: Lorenzo Colitti Signed-off-by: Richard Weinberger

um: Switch clocksource to hrtimers

2015-11-06T21:54:49+00:00

UML is using an obsolete itimer call for all timers and "polls" for kernel space timer firing in its userspace portion resulting in a long list of bugs and incorrect behaviour(s). It also uses ITIMER_VIRTUAL for its timer which results in the timer being dependent on it running and the cpu load. This patch fixes this by moving to posix high resolution timers firing off CLOCK_MONOTONIC and relaying the timer correctly to the UML userspace. Fixes: - crashes when hosts suspends/resumes - broken userspace timers - effecive ~40Hz instead of what they should be. Note - this modifies skas behavior by no longer setting an itimer per clone(). Timer events are relayed instead. - kernel network packet scheduling disciplines - tcp behaviour especially under load - various timer related corner cases Finally, overall responsiveness of userspace is better. Signed-off-by: Thomas Meyer Signed-off-by: Anton Ivanov [rw: massaged commit message] Signed-off-by: Richard Weinberger

um: Fix out-of-tree build

2015-10-19T20:53:36+00:00

Commit 30b11ee9a (um: Remove copy&paste code from init.h) uncovered an issue wrt. out-of-tree builds. For out-of-tree builds, we must not rely on relative paths. Before 30b11ee9a it worked by chance as no host code included generated header files. Acked-by: Randy Dunlap Signed-off-by: Richard Weinberger

um: Stop abusing KERNEL

2015-05-31T20:05:32+00:00

Currently UML is abusing __KERNEL__ to distinguish between kernel and host code (os-Linux). It is better to use a custom define such that existing users of __KERNEL__ don't get confused. Signed-off-by: Richard Weinberger

kbuild: use relative path more to include Makefile

2015-04-02T14:42:08+00:00

Prior to this commit, it was impossible to use relative path to include Makefiles from the top level Makefile because the option "--include-dir=$(srctree)" becomes effective when Make enters into sub Makefiles. To use relative path in any places, this commit moves the option above the "sub-make" target. Signed-off-by: Masahiro Yamada Signed-off-by: Michal Marek

um: Fix for relative objtree when generating x86 headers

2014-06-05T15:55:48+00:00

In an O= build, rely on the generated Makefile to call the main Makefile properly. When building in the source tree, we do not need to specify the -C and O= either. This fixes the problem when $(objtree) is a relative path and the -C changes the directory. Reported-by: Richard Weinberger Signed-off-by: Michal Marek