On 10 November 2014 05:11, Mark Salter <msalter@xxxxxxxxxx> wrote: > On Thu, 2014-11-06 at 15:13 +0100, Ard Biesheuvel wrote: >> This changes the way memblocks are installed based on the contents of >> the UEFI memory map. Formerly, all regions would be memblock_add()'ed, >> after which unusable regions would be memblock_reserve()'d as well. >> To simplify things, but also to allow access to the unusable regions >> through mmap(/dev/mem), even with CONFIG_STRICT_DEVMEM set, change >> this so that only usable regions are memblock_add()'ed in the first >> place. > > This patch is crashing 64K pagesize kernels during boot. I'm not exactly > sure why, though. Here is what I get on an APM Mustang box: > Ah, yes, I meant to mention this patch https://git.kernel.org/cgit/linux/kernel/git/glikely/linux.git/commit/?id=8cccffc52694938fc88f3d90bc7fed8460e27191 in the cover letter, which addresses this issue at least for the DT case. -- Ard. > [ 0.046262] Unhandled fault: alignment fault (0x96000021) at 0xfffffc000004f026 > [ 0.053863] Internal error: : 96000021 [#1] SMP > [ 0.058566] Modules linked in: > [ 0.061736] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.18.0-rc3+ #11 > [ 0.068418] Hardware name: APM X-Gene Mustang board (DT) > [ 0.073942] task: fffffe0000f46a20 ti: fffffe0000f10000 task.ti: fffffe0000f10000 > [ 0.081735] PC is at acpi_ns_lookup+0x520/0x734 > [ 0.086448] LR is at acpi_ns_lookup+0x4ac/0x734 > [ 0.091151] pc : [<fffffe0000460458>] lr : [<fffffe00004603e4>] pstate: 60000245 > [ 0.098843] sp : fffffe0000f13b00 > [ 0.102293] x29: fffffe0000f13b10 x28: 000000000000000a > [ 0.107810] x27: 0000000000000008 x26: 0000000000000000 > [ 0.113345] x25: fffffe0000f13c38 x24: fffffe0000fae000 > [ 0.118862] x23: 0000000000000008 x22: 0000000000000001 > [ 0.124406] x21: fffffe0000972000 x20: 000000000000000a > [ 0.129940] x19: fffffc000004f026 x18: 000000000000000b > [ 0.135483] x17: 0000000000000023 x16: 000000000000059f > [ 0.141026] x15: 0000000000007fff x14: 000000000000038e > [ 0.146543] x13: ff00000000000000 x12: ffffffffffffffff > [ 0.152060] x11: 0000000000000010 x10: 00000000fffffff6 > [ 0.157585] x9 : 0000000000000050 x8 : fffffe03fa7401b0 > [ 0.163111] x7 : fffffe0001115a00 x6 : fffffe0001115a00 > [ 0.168620] x5 : fffffe0001115000 x4 : 0000000000000010 > [ 0.174146] x3 : 0000000000000010 x2 : 000000000000000b > [ 0.179689] x1 : 00000000fffffff5 x0 : 0000000000000000 > [ 0.185215] > [ 0.186765] Process swapper/0 (pid: 0, stack limit = 0xfffffe0000f10058) > [ 0.193724] Stack: (0xfffffe0000f13b00 to 0xfffffe0000f14000) > [ 0.199707] 3b00: 00000000 fffffe03 00000666 00000000 00f13bd0 fffffe00 0044f388 fffffe00 > ... > [ 0.539605] Call trace: > [ 0.542150] [<fffffe0000460458>] acpi_ns_lookup+0x520/0x734 > [ 0.547935] [<fffffe000044f384>] acpi_ds_load1_begin_op+0x384/0x4b4 > [ 0.554445] [<fffffe0000469594>] acpi_ps_build_named_op+0xfc/0x228 > [ 0.560868] [<fffffe00004698c8>] acpi_ps_create_op+0x208/0x340 > [ 0.566945] [<fffffe0000468ea8>] acpi_ps_parse_loop+0x208/0x7f8 > [ 0.573092] [<fffffe000046a6b8>] acpi_ps_parse_aml+0x1c0/0x434 > [ 0.579153] [<fffffe0000463cb0>] acpi_ns_one_complete_parse+0x1a4/0x1ec > [ 0.586017] [<fffffe0000463d88>] acpi_ns_parse_table+0x90/0x130 > [ 0.592181] [<fffffe0000462f94>] acpi_ns_load_table+0xc8/0x1b0 > [ 0.598243] [<fffffe0000e71848>] acpi_load_tables+0xf4/0x234 > [ 0.604122] [<fffffe0000e70a0c>] acpi_early_init+0x78/0xc8 > [ 0.609828] [<fffffe0000e40928>] start_kernel+0x334/0x3ac > [ 0.615431] Code: 2a00037b b9009fbc 36180057 321d037b (b9400260) > [ 0.621777] ---[ end trace cb88537fdc8fa200 ]--- > [ 0.626586] Kernel panic - not syncing: Attempted to kill the idle task! > > I also get a different crash when booting with device tree instead of ACPI. > > One thing is that early_init_dt_add_memory_arch() is called with UEFI > (4K) pagesize alignment and size and it clips the passed in range such > that what is added is the 64K aligned range which fits completely within > the given range. This may mean nothing gets added if the given range is > smaller than 64K. And only a subset of the desired range is added in > other cases. This could theoretically leave bits of devicetree and/or > initrd unmapped, but that doesn't seem to be the case here. I'll keep > poking at it... > >> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> >> --- >> arch/arm64/kernel/efi.c | 69 +++++++++++++++++++------------------------------ >> 1 file changed, 26 insertions(+), 43 deletions(-) >> >> diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c >> index 3009c22e2620..af2214c692d3 100644 >> --- a/arch/arm64/kernel/efi.c >> +++ b/arch/arm64/kernel/efi.c >> @@ -40,13 +40,6 @@ static int __init uefi_debug_setup(char *str) >> } >> early_param("uefi_debug", uefi_debug_setup); >> >> -static int __init is_normal_ram(efi_memory_desc_t *md) >> -{ >> - if (md->attribute & EFI_MEMORY_WB) >> - return 1; >> - return 0; >> -} >> - >> static int __init uefi_init(void) >> { >> efi_char16_t *c16; >> @@ -105,28 +98,11 @@ out: >> return retval; >> } >> >> -/* >> - * Return true for RAM regions we want to permanently reserve. >> - */ >> -static __init int is_reserve_region(efi_memory_desc_t *md) >> -{ >> - switch (md->type) { >> - case EFI_LOADER_CODE: >> - case EFI_LOADER_DATA: >> - case EFI_BOOT_SERVICES_CODE: >> - case EFI_BOOT_SERVICES_DATA: >> - case EFI_CONVENTIONAL_MEMORY: >> - return 0; >> - default: >> - break; >> - } >> - return is_normal_ram(md); >> -} >> - >> -static __init void reserve_regions(void) >> +static __init void process_memory_map(void) >> { >> efi_memory_desc_t *md; >> u64 paddr, npages, size; >> + u32 lost = 0; >> >> if (uefi_debug) >> pr_info("Processing EFI memory map:\n"); >> @@ -134,31 +110,38 @@ static __init void reserve_regions(void) >> for_each_efi_memory_desc(&memmap, md) { >> paddr = md->phys_addr; >> npages = md->num_pages; >> + size = npages << EFI_PAGE_SHIFT; >> >> if (uefi_debug) { >> char buf[64]; >> >> - pr_info(" 0x%012llx-0x%012llx %s", >> - paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1, >> + pr_info(" 0x%012llx-0x%012llx %s\n", >> + paddr, paddr + size - 1, >> efi_md_typeattr_format(buf, sizeof(buf), md)); >> } >> >> - memrange_efi_to_native(&paddr, &npages); >> - size = npages << PAGE_SHIFT; >> - >> - if (is_normal_ram(md)) >> - early_init_dt_add_memory_arch(paddr, size); >> - >> - if (is_reserve_region(md)) { >> - memblock_reserve(paddr, size); >> - if (uefi_debug) >> - pr_cont("*"); >> - } >> - >> - if (uefi_debug) >> - pr_cont("\n"); >> + if (!efi_mem_is_usable_region(md)) >> + continue; >> + >> + early_init_dt_add_memory_arch(paddr, size); >> + >> + /* >> + * Keep a tally of how much memory we are losing due to >> + * rounding of regions that are not aligned to the page >> + * size. We cannot easily recover this memory without >> + * sorting the memory map and attempting to merge adjacent >> + * usable regions. >> + */ >> + if (PAGE_SHIFT != EFI_PAGE_SHIFT) >> + lost += (npages << EFI_PAGE_SHIFT) - >> + round_down(max_t(s64, size - PAGE_ALIGN(paddr) + >> + md->phys_addr, 0), >> + PAGE_SIZE); >> } >> >> + if (lost > SZ_1K) >> + pr_warn("efi: lost %u KB of RAM to rounding\n", lost / SZ_1K); >> + >> set_bit(EFI_MEMMAP, &efi.flags); >> } >> >> @@ -182,7 +165,7 @@ void __init efi_init(void) >> >> WARN_ON(uefi_init() < 0); >> >> - reserve_regions(); >> + process_memory_map(); >> } >> >> static int __init arm64_enter_virtual_mode(void) > > -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
