Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751607AbdIOK60 (ORCPT ); Fri, 15 Sep 2017 06:58:26 -0400 Received: from mail-pg0-f43.google.com ([74.125.83.43]:51344 "EHLO mail-pg0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751575AbdIOK6Y (ORCPT ); Fri, 15 Sep 2017 06:58:24 -0400 X-Google-Smtp-Source: ADKCNb7jgGIBgrA6lR9yOUQuY9/64uTXrsHhjdDRG7a3DzRlT3TqKfFPr7pmZCcgI+sJxtASXBq3WQ== From: AKASHI Takahiro To: catalin.marinas@arm.com, will.deacon@arm.com, bauerman@linux.vnet.ibm.com, dhowells@redhat.com, vgoyal@redhat.com, herbert@gondor.apana.org.au, davem@davemloft.net, akpm@linux-foundation.org, mpe@ellerman.id.au, dyoung@redhat.com, bhe@redhat.com, arnd@arndb.de, ard.biesheuvel@linaro.org Cc: kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, AKASHI Takahiro Subject: [PATCH v3 06/10] arm64: kexec_file: create purgatory Date: Fri, 15 Sep 2017 19:59:28 +0900 Message-Id: <20170915105932.25338-7-takahiro.akashi@linaro.org> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20170915105932.25338-1-takahiro.akashi@linaro.org> References: <20170915105932.25338-1-takahiro.akashi@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3610 Lines: 128 This is a basic purgatory, or a kind of glue code between the two kernels, for arm64. Since purgatory is assumed to be relocatable (not executable) object by kexec generic code, arch_kexec_apply_relocations_add() is required in general. Arm64's purgatory, however, is a simple asm and all the references can be resolved as local, no re-linking is needed here. Please note that even if we don't support digest check at purgatory we need purgatory_sha_regions and purgatory_sha256_digest as they are referenced by generic kexec code. Signed-off-by: AKASHI Takahiro Cc: Catalin Marinas Cc: Will Deacon --- arch/arm64/Makefile | 1 + arch/arm64/purgatory/Makefile | 24 +++++++++++++++++++ arch/arm64/purgatory/entry.S | 55 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 80 insertions(+) create mode 100644 arch/arm64/purgatory/Makefile create mode 100644 arch/arm64/purgatory/entry.S diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 9b41f1e3b1a0..429f60728c0a 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -105,6 +105,7 @@ core-$(CONFIG_XEN) += arch/arm64/xen/ core-$(CONFIG_CRYPTO) += arch/arm64/crypto/ libs-y := arch/arm64/lib/ $(libs-y) core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a +core-$(CONFIG_KEXEC_FILE) += arch/arm64/purgatory/ # Default target when executing plain make boot := arch/arm64/boot diff --git a/arch/arm64/purgatory/Makefile b/arch/arm64/purgatory/Makefile new file mode 100644 index 000000000000..c2127a2cbd51 --- /dev/null +++ b/arch/arm64/purgatory/Makefile @@ -0,0 +1,24 @@ +OBJECT_FILES_NON_STANDARD := y + +purgatory-y := entry.o + +targets += $(purgatory-y) +PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y)) + +LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined \ + -nostdlib -z nodefaultlib +targets += purgatory.ro + +$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE + $(call if_changed,ld) + +targets += kexec_purgatory.c + +CMD_BIN2C = $(objtree)/scripts/basic/bin2c +quiet_cmd_bin2c = BIN2C $@ + cmd_bin2c = $(CMD_BIN2C) kexec_purgatory < $< > $@ + +$(obj)/kexec_purgatory.c: $(obj)/purgatory.ro FORCE + $(call if_changed,bin2c) + +obj-${CONFIG_KEXEC_FILE} += kexec_purgatory.o diff --git a/arch/arm64/purgatory/entry.S b/arch/arm64/purgatory/entry.S new file mode 100644 index 000000000000..fe6e968076db --- /dev/null +++ b/arch/arm64/purgatory/entry.S @@ -0,0 +1,55 @@ +/* + * kexec core purgatory + */ +#include +#include + +#define SHA256_DIGEST_SIZE 32 /* defined in crypto/sha.h */ + +.text + +ENTRY(purgatory_start) + /* Start new image. */ + ldr x17, __kernel_entry + ldr x0, __dtb_addr + mov x1, xzr + mov x2, xzr + mov x3, xzr + br x17 +END(purgatory_start) + +/* + * data section: + * kernel_entry and dtb_addr are global but also labelled as local, + * "__xxx:", to avoid unwanted re-linking. + * + * purgatory_sha_regions and purgatory_sha256_digest are referenced + * by kexec generic code and so must exist, but not actually used + * here because hash check is not that useful in purgatory. + */ +.align 3 + +.globl kernel_entry +kernel_entry: +__kernel_entry: + .quad 0 +END(kernel_entry) + +.globl dtb_addr +dtb_addr: +__dtb_addr: + .quad 0 +END(dtb_addr) + +.globl purgatory_sha_regions +purgatory_sha_regions: + .rept KEXEC_SEGMENT_MAX + .quad 0 + .quad 0 + .endr +END(purgatory_sha_regions) + +.globl purgatory_sha256_digest +purgatory_sha256_digest: + .skip SHA256_DIGEST_SIZE +END(purgatory_sha256_digest) -- 2.14.1