On Wed, Aug 26, 2015 at 10:06:30AM +0200, Ard Biesheuvel wrote: > There are two problems with the UEFI stub DT memory node removal > routine: > - it deletes nodes as it traverses the tree, which happens to work > but is not supported, as deletion invalidates the node iterator; > - deleting memory nodes entirely may discard annotations in the form > of additional properties on the nodes. > > Now that the UEFI initialization has moved to an earlier stage, we can > actually just ignore any memblocks that are installed after we have > processed the UEFI memory map. This way, it is no longer necessary to > remove the nodes, so we can remove that logic from the stub as well. > > Signed-off-by: Ard Biesheuvel <[email protected]> > --- > arch/arm64/mm/init.c | 10 ++++++++ > drivers/firmware/efi/libstub/fdt.c | 24 +------------------- > 2 files changed, 11 insertions(+), 23 deletions(-)
Nice cleanup. Acked-by: Leif Lindholm <[email protected]> > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index ab25fde7397c..ecbc051bc66b 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -379,6 +379,16 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 > size) > { > const u64 phys_offset = __pa(PAGE_OFFSET); > > + /* > + * This callback will be invoked both when booting via UEFI and when > + * booting via DT only. In the former case, we need to ignore memory > + * nodes in the DT since UEFI is authoritative when it comes to the > + * memory map. So ignore any invocations of this callback after > + * EFI_MEMMAP has been set. > + */ > + if (efi_enabled(EFI_MEMMAP)) > + return; > + > if (!PAGE_ALIGNED(base)) { > if (size < PAGE_SIZE - (base & ~PAGE_MASK)) { > pr_warn("Ignoring memory block 0x%llx - 0x%llx\n", > diff --git a/drivers/firmware/efi/libstub/fdt.c > b/drivers/firmware/efi/libstub/fdt.c > index ef5d764e2a27..343e7992bd8f 100644 > --- a/drivers/firmware/efi/libstub/fdt.c > +++ b/drivers/firmware/efi/libstub/fdt.c > @@ -24,7 +24,7 @@ efi_status_t update_fdt(efi_system_table_t *sys_table, void > *orig_fdt, > unsigned long map_size, unsigned long desc_size, > u32 desc_ver) > { > - int node, prev, num_rsv; > + int node, num_rsv; > int status; > u32 fdt_val32; > u64 fdt_val64; > @@ -54,28 +54,6 @@ efi_status_t update_fdt(efi_system_table_t *sys_table, > void *orig_fdt, > goto fdt_set_fail; > > /* > - * Delete any memory nodes present. We must delete nodes which > - * early_init_dt_scan_memory may try to use. > - */ > - prev = 0; > - for (;;) { > - const char *type; > - int len; > - > - node = fdt_next_node(fdt, prev, NULL); > - if (node < 0) > - break; > - > - type = fdt_getprop(fdt, node, "device_type", &len); > - if (type && strncmp(type, "memory", len) == 0) { > - fdt_del_node(fdt, node); > - continue; > - } > - > - prev = node; > - } > - > - /* > * Delete all memory reserve map entries. When booting via UEFI, > * kernel will use the UEFI memory map to find reserved regions. > */ > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
