Messages in this thread | | | From | Junichi Nomura <> | Subject | Re: [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel | Date | Mon, 15 Apr 2019 23:00:25 +0000 |
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On 4/15/19 7:25 PM, Borislav Petkov wrote: > On Mon, Apr 15, 2019 at 11:07:17AM +0200, Borislav Petkov wrote: >> On Mon, Apr 15, 2019 at 07:01:54AM +0000, Junichi Nomura wrote: >>> OK. Then I'll go back to v3 and make sure to hang when >>> something is wrong during kexec boot on EFI system. >> >> No need - I have it here locally. I'll clean it up and post it for >> review. > > Here it is. Ok, not ok?
Thank you. Basically ok. I put some comments below about whether to hang or return.
> +static acpi_physical_address kexec_get_rsdp_addr(void) > +{ > + efi_system_table_64_t *systab; > + struct efi_setup_data *esd; > + struct efi_info *ei; > + char *sig; > + > + esd = (struct efi_setup_data *)get_kexec_setup_data_addr(); > + if (!esd) > + return 0; > + > + if (!esd->tables) { > + debug_putstr("Wrong kexec SETUP_EFI data.\n"); > + return 0; > + }
I thought we should hang here instead of return so that we don't run into efi_get_rsdp_addr() in case of kexec.
> + ei = &boot_params->efi_info; > + sig = (char *)&ei->efi_loader_signature; > + if (strncmp(sig, EFI64_LOADER_SIGNATURE, 4)) { > + debug_putstr("Wrong kexec EFI loader signature.\n"); > + return 0; > + }
Same here.
> + /* Get systab from boot params. */ > + systab = (efi_system_table_64_t *) (ei->efi_systab | ((__u64)ei->efi_systab_hi << 32)); > + if (!systab) > + error("EFI system table not found in kexec boot_params."); > + > + return __efi_get_rsdp_addr((unsigned long)esd->tables, systab->nr_tables, true);
Same here when __efi_get_rsdp_addr() returns 0.
I'm fine with either way, though.
-- Jun'ichi Nomura, NEC Corporation / NEC Solution Innovators, Ltd. | |