> > > On 64-bit kernels we currently have a 512 byte struct paca_struct for > > > each cpu (usually just called "the paca"). Currently they are staticall= > y > > > allocated, which means a kernel built for a large number of cpus will > > > waste a lot of space if it's booted on a machine with few cpus. > > >=20 > > > We can avoid that by only allocating the number of pacas we need at > > > boot. However this is complicated by the fact that we need to access > > > the paca before we know how many cpus there are in the system. > > >=20 > > > The solution is to dynamically allocate enough space for NR_CPUS pacas, > > > but then later in boot when we know how many cpus we have, we free any > > > unused pacas. > > >=20 > > > Lightly booted on Legacy iSeries & pSeries LPAR. > > >=20 > > > Signed-off-by: Michael Ellerman <mich...@ellerman.id.au> > >=20 > > <snip> > >=20 > > > --- a/arch/powerpc/kernel/setup-common.c > > > +++ b/arch/powerpc/kernel/setup-common.c > > > @@ -493,6 +493,8 @@ void __init smp_setup_cpu_maps(void) > > > * here will have to be reworked > > > */ > > > cpu_init_thread_core_maps(nthreads); > > > + > > > + free_unused_pacas(); > >=20 > > This is still barfing for me on 32bit. > > Darn, what config? I built at least one :)
I think I used mpc86xx_defconfig. > > Putting an #include <asm/paca.h> at the top of setup-common.c fixes it. > > Gah, I saw it was coming via somewhere else but decided not to add it, > wrong decision :) IMHO, if it's used we should put it in. Otherwise some other random include file will remove it and break us. Mikey _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
