| Message ID | 1227650039.7434.33.camel@localhost.localdomain (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Tue, 2008-11-25 at 15:53 -0600, Hollis Blanchard wrote: > On Tue, 2008-11-25 at 11:10 +1100, Michael Ellerman wrote: > > > > Still, I think it would be better to only set memory_limit when the mem > > size is not a multiple of the PAGE_SIZE - so that memory_limit retains > > it's function as both the value of the limit and a boolean. > > OK, how's this? > > ppc: force memory size to be a multiple of PAGE_SIZE > > Ensure that total memory size is page-aligned, because otherwise > mark_bootmem() gets upset. > > This error case was triggered by using 64 KiB pages in the kernel while > arch/powerpc/boot/4xx.c arbitrarily reduced the amount of memory by 4096 (to > work around a chip bug that affects the last 256 bytes of physical memory). > > Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com> > > diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c > --- a/arch/powerpc/kernel/prom.c > +++ b/arch/powerpc/kernel/prom.c > @@ -1160,6 +1160,8 @@ static inline void __init phyp_dump_rese > > void __init early_init_devtree(void *params) > { > + unsigned long limit, memsize; > + > DBG(" -> early_init_devtree(%p)\n", params); > > /* Setup flat device-tree pointer */ > @@ -1200,7 +1202,15 @@ void __init early_init_devtree(void *par > early_reserve_mem(); > phyp_dump_reserve_mem(); I was thinking more like the following: > > - lmb_enforce_memory_limit(memory_limit); > + limit = memory_limit; > + if (! limit) { > + /* Ensure that total memory size is page-aligned, because > + * otherwise mark_bootmem() gets upset. */ > + lmb_analyze(); memsize = lmb_phys_mem_size(); if(memsize & PAGE_MASK != memsize) limit = memsize & PAGE_MASK; > + } > + lmb_enforce_memory_limit(limit); > + So that we never needlessly run through the enforce code with limit = memsize. But maybe it's a bit pedantic. cheers
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -1160,6 +1160,8 @@ static inline void __init phyp_dump_rese void __init early_init_devtree(void *params) { + unsigned long limit; + DBG(" -> early_init_devtree(%p)\n", params); /* Setup flat device-tree pointer */ @@ -1200,7 +1202,15 @@ void __init early_init_devtree(void *par early_reserve_mem(); phyp_dump_reserve_mem(); - lmb_enforce_memory_limit(memory_limit); + limit = memory_limit; + if (! limit) { + /* Ensure that total memory size is page-aligned, because + * otherwise mark_bootmem() gets upset. */ + lmb_analyze(); + limit = lmb_phys_mem_size() & PAGE_MASK; + } + lmb_enforce_memory_limit(limit); + lmb_analyze(); DBG("Phys. mem: %lx\n", lmb_phys_mem_size());