----- Original Message ----- > From: "Richard Weinberger" <rich...@nod.at> > To: user-mode-linux-de...@lists.sourceforge.net > Cc: a...@arndb.de, mik...@szeredi.hu, "Richard Weinberger" <rich...@nod.at>, > linux-kernel@vger.kernel.org, > ge...@linux-m68k.org, lf...@altera.com > Sent: Wednesday, December 10, 2014 1:02:15 PM > Subject: [uml-devel] [PATCH] um: Skip futex_atomic_cmpxchg_inatomic() test > > futex_atomic_cmpxchg_inatomic() does not work on UML because > it triggers a copy_from_user() in kernel context. > On UML copy_from_user() can only be used if the kernel was called > by a real user space process such that UML can use ptrace() > to fetch the value. > > Reported-by: Miklos Szeredi <mik...@szeredi.hu> > Suggested-by: Geert Uytterhoeven <ge...@linux-m68k.org> > Signed-off-by: Richard Weinberger <rich...@nod.at> > --- > arch/um/Kconfig.common | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common > index 87bc868..d195a87 100644 > --- a/arch/um/Kconfig.common > +++ b/arch/um/Kconfig.common > @@ -3,6 +3,7 @@ config UML > default y > select HAVE_ARCH_AUDITSYSCALL > select HAVE_UID16 > + select HAVE_FUTEX_CMPXCHG if FUTEX > select GENERIC_IRQ_SHOW > select GENERIC_CPU_DEVICES > select GENERIC_IO > -- > 2.1.0 > Hi,
tested it a few days, looks good. Tested-by: Daniel Walter <d.wal...@0x90.at> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
