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charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Christophe Leroy writes: > Le 21/08/2019 =C3=A0 14:15, Segher Boessenkool a =C3=A9crit=C2=A0: >> On Wed, Aug 21, 2019 at 01:50:52PM +0200, Christophe Leroy wrote: >>> Do you have any idea on how to avoid that bcl/mflr stuff ? >>=20 >> Do a load from some fixed address? Maybe an absolute address, even? >> lwz r3,-12344(0) or similar (that address is in kernel space...) >>=20 >> There aren't many options, and certainly not many *good* options! >>=20 > > IIUC, the VDSO is seen by apps the same way as a dynamic lib. Couldn't=20 > the relocation be done only once when the app loads the VDSO as for a=20 > regular .so lib ? How does address space randomization work for .so libs? > > It looks like it is what others do, at least x86 and arm64, unless I=20 > misunderstood their code. > > Christophe