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Sun, 17 Jun 2018 23:43:36 -0700 (PDT) Date: Mon, 18 Jun 2018 15:44:14 +0900 From: AKASHI Takahiro To: James Morse Cc: catalin.marinas@arm.com, will.deacon@arm.com, akpm@linux-foundation.org, ard.biesheuvel@linaro.org, tbaicar@codeaurora.org, bhsharma@redhat.com, dyoung@redhat.com, mark.rutland@arm.com, al.stone@linaro.org, graeme.gregory@linaro.org, hanjun.guo@linaro.org, lorenzo.pieralisi@arm.com, sudeep.holla@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org Subject: Re: [PATCH 2/3] arm64: acpi,efi: fix alignment fault in accessing ACPI tables at kdump Message-ID: <20180618064413.GF23681@linaro.org> Mail-Followup-To: AKASHI Takahiro , James Morse , catalin.marinas@arm.com, will.deacon@arm.com, akpm@linux-foundation.org, ard.biesheuvel@linaro.org, tbaicar@codeaurora.org, bhsharma@redhat.com, dyoung@redhat.com, mark.rutland@arm.com, al.stone@linaro.org, graeme.gregory@linaro.org, hanjun.guo@linaro.org, lorenzo.pieralisi@arm.com, sudeep.holla@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org References: <20180615075623.13454-1-takahiro.akashi@linaro.org> <20180615075623.13454-3-takahiro.akashi@linaro.org> <026a4d23-ac91-ed35-d711-c55882242037@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <026a4d23-ac91-ed35-d711-c55882242037@arm.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org James, On Fri, Jun 15, 2018 at 05:30:08PM +0100, James Morse wrote: > Hi Akashi, > > On 15/06/18 08:56, AKASHI Takahiro wrote: > > This is a fix against the issue that crash dump kernel may hang up > > during booting, which can happen on any ACPI-based system with "ACPI > > Reclaim Memory." > > > > (kernel messages after panic kicked off kdump) > > (snip...) > > Bye! > > (snip...) > > ACPI: Core revision 20170728 > > pud=000000002e7d0003, *pmd=000000002e7c0003, *pte=00e8000039710707 > > Internal error: Oops: 96000021 [#1] SMP > > Modules linked in: > > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.0-rc6 #1 > > task: ffff000008d05180 task.stack: ffff000008cc0000 > > PC is at acpi_ns_lookup+0x25c/0x3c0 > > LR is at acpi_ds_load1_begin_op+0xa4/0x294 > > (snip...) > > Process swapper/0 (pid: 0, stack limit = 0xffff000008cc0000) > > Call trace: > > (snip...) > > [] acpi_ns_lookup+0x25c/0x3c0 > > [] acpi_ds_load1_begin_op+0xa4/0x294 > > [] acpi_ps_build_named_op+0xc4/0x198 > > [] acpi_ps_create_op+0x14c/0x270 > > [] acpi_ps_parse_loop+0x188/0x5c8 > > [] acpi_ps_parse_aml+0xb0/0x2b8 > > [] acpi_ns_one_complete_parse+0x144/0x184 > > [] acpi_ns_parse_table+0x48/0x68 > > [] acpi_ns_load_table+0x4c/0xdc > > [] acpi_tb_load_namespace+0xe4/0x264 > > [] acpi_load_tables+0x48/0xc0 > > [] acpi_early_init+0x9c/0xd0 > > [] start_kernel+0x3b4/0x43c > > Code: b9008fb9 2a000318 36380054 32190318 (b94002c0) > > ---[ end trace c46ed37f9651c58e ]--- > > Kernel panic - not syncing: Fatal exception > > Rebooting in 10 seconds.. > > > > (diagnosis) > > * This fault is a data abort, alignment fault (ESR=0x96000021) > > during reading out ACPI table. > > * Initial ACPI tables are normally stored in system ram and marked as > > "ACPI Reclaim memory" by the firmware. > > * After the commit f56ab9a5b73c ("efi/arm: Don't mark ACPI reclaim > > memory as MEMBLOCK_NOMAP"), those regions are differently handled > > as they are "memblock-reserved", without NOMAP bit. > > * So they are now excluded from device tree's "usable-memory-range" > > which kexec-tools determines based on a current view of /proc/iomem. > > * When crash dump kernel boots up, it tries to accesses ACPI tables by > > mapping them with ioremap(), not ioremap_cache(), in acpi_os_ioremap() > > since they are no longer part of mapped system ram. > > * Given that ACPI accessor/helper functions are compiled in without > > unaligned access support (ACPI_MISALIGNMENT_NOT_SUPPORTED), > > any unaligned access to ACPI tables can cause a fatal panic. > > > > With this patch, acpi_os_ioremap() always honors memory attribute > > information provided by the firmware (EFI) and retaining cacheability > > allows the kernel safe access to ACPI tables. > > > > Please note that arm_enable_runtime_services() is now renamed to > > efi_enter_virtual_mode() due to the similarity to x86's. > > Just a rename?: and maps EFI memory map whether or not runtime service is enabled. > > drivers/firmware/efi/arm-runtime.c | 27 ++++++++++++--------------- > > > > > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > > index 32f465a80e4e..d53c95f4e1a9 100644 > > --- a/arch/arm64/include/asm/acpi.h > > +++ b/arch/arm64/include/asm/acpi.h > > @@ -29,18 +31,22 @@ > > > > /* Basic configuration for ACPI */ > > #ifdef CONFIG_ACPI > > +pgprot_t __acpi_get_mem_attribute(phys_addr_t addr); > > + > > /* ACPI table mapping after acpi_permanent_mmap is set */ > > static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys, > > acpi_size size) > > { > > + /* For normal memory we already have a cacheable mapping. */ > > + if (memblock_is_map_memory(phys)) > > + return (void __iomem *)__phys_to_virt(phys); > > > /* > > - * EFI's reserve_regions() call adds memory with the WB attribute > > - * to memblock via early_init_dt_add_memory_arch(). > > + * We should still honor the memory's attribute here because > > + * crash dump kernel possibly excludes some ACPI (reclaim) > > + * regions from memblock list. > > */ > > (Even without kdump we would still need this. Regions ACPI wants mapped may not > be covered by the linear map. In this case we need to use the attributes > firmware described in the UEFI memory map. Kdump exacerbates this by > artificially reducing the range of the linear map.) > > > > - if (!memblock_is_memory(phys)) > > - return ioremap(phys, size); > > - > > - return ioremap_cache(phys, size); > > + return __ioremap(phys, size, __acpi_get_mem_attribute(phys)); > > } > > > > > diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c > > index 5889cbea60b8..566ef0a9edb5 100644 > > --- a/drivers/firmware/efi/arm-runtime.c > > +++ b/drivers/firmware/efi/arm-runtime.c > > @@ -106,46 +106,43 @@ static bool __init efi_virtmap_init(void) > > * non-early mapping of the UEFI system table and virtual mappings for all > > * EFI_MEMORY_RUNTIME regions. > > */ > > -static int __init arm_enable_runtime_services(void) > > +void __init efi_enter_virtual_mode(void) > > { > > u64 mapsize; > > > > if (!efi_enabled(EFI_BOOT)) { > > pr_info("EFI services will not be available.\n"); > > - return 0; > > + return; > > + } > > + > > + mapsize = efi.memmap.desc_size * efi.memmap.nr_map; > > + > > + if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { > > + pr_err("Failed to remap EFI memory map\n"); > > + return; > > } > > > > if (efi_runtime_disabled()) { > > pr_info("EFI runtime services will be disabled.\n"); > > - return 0; > > + return; > > } > > > > if (efi_enabled(EFI_RUNTIME_SERVICES)) { > > pr_info("EFI runtime services access via paravirt.\n"); > > - return 0; > > + return; > > } > > > > pr_info("Remapping and enabling EFI services.\n"); > > > > - mapsize = efi.memmap.desc_size * efi.memmap.nr_map; > > - > > - if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { > > - pr_err("Failed to remap EFI memory map\n"); > > - return -ENOMEM; > > - } > > - > > if (!efi_virtmap_init()) { > > pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n"); > > - return -ENOMEM; > > + return; > > } > > > > /* Set up runtime services function pointers */ > > efi_native_runtime_setup(); > > set_bit(EFI_RUNTIME_SERVICES, &efi.flags); > > - > > - return 0; > > } > > Please have the drivers/firmware/efi/arm-runtime.c changes in a separate patch > (maybe combine it with patch 3). The 'efi/arm: ' prefix is more likely to catch > the maintainers attention. > > I think this is what Ard meant by: > | Could you please move the changes to this file and init/main.c into a > | separate patch? > > https://patchwork.kernel.org/patch/10361761/ > > > > -early_initcall(arm_enable_runtime_services); > > With just this patch, surely nothing ever calls arm_enable_runtime_services(), > and now acpi_os_ioremap() will return device memory for anything that isn't part > of the linear region. (This breaks RAS). Actually I noticed the issue. > This will make it difficult to bisect through for any RAS or > efi-runtime-services issue. Its easily fixed: please put the efi+init changes in > a patch before the acpi_os_ioremap() changes. I was reluctant to put different part of code changes into one. But if nobody cares, I will do so in three patches. * change arm_enable_runtime_services() with renaming * move this function earlier in start_kernel() * modify acpi_os_ioremap() Thanks, -Takahiro AKASHI > Otherwise, looks good to me! > > > Thanks, > > James From mboxrd@z Thu Jan 1 00:00:00 1970 From: takahiro.akashi@linaro.org (AKASHI Takahiro) Date: Mon, 18 Jun 2018 15:44:14 +0900 Subject: [PATCH 2/3] arm64: acpi,efi: fix alignment fault in accessing ACPI tables at kdump In-Reply-To: <026a4d23-ac91-ed35-d711-c55882242037@arm.com> References: <20180615075623.13454-1-takahiro.akashi@linaro.org> <20180615075623.13454-3-takahiro.akashi@linaro.org> <026a4d23-ac91-ed35-d711-c55882242037@arm.com> Message-ID: <20180618064413.GF23681@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org James, On Fri, Jun 15, 2018 at 05:30:08PM +0100, James Morse wrote: > Hi Akashi, > > On 15/06/18 08:56, AKASHI Takahiro wrote: > > This is a fix against the issue that crash dump kernel may hang up > > during booting, which can happen on any ACPI-based system with "ACPI > > Reclaim Memory." > > > > (kernel messages after panic kicked off kdump) > > (snip...) > > Bye! > > (snip...) > > ACPI: Core revision 20170728 > > pud=000000002e7d0003, *pmd=000000002e7c0003, *pte=00e8000039710707 > > Internal error: Oops: 96000021 [#1] SMP > > Modules linked in: > > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.0-rc6 #1 > > task: ffff000008d05180 task.stack: ffff000008cc0000 > > PC is at acpi_ns_lookup+0x25c/0x3c0 > > LR is at acpi_ds_load1_begin_op+0xa4/0x294 > > (snip...) > > Process swapper/0 (pid: 0, stack limit = 0xffff000008cc0000) > > Call trace: > > (snip...) > > [] acpi_ns_lookup+0x25c/0x3c0 > > [] acpi_ds_load1_begin_op+0xa4/0x294 > > [] acpi_ps_build_named_op+0xc4/0x198 > > [] acpi_ps_create_op+0x14c/0x270 > > [] acpi_ps_parse_loop+0x188/0x5c8 > > [] acpi_ps_parse_aml+0xb0/0x2b8 > > [] acpi_ns_one_complete_parse+0x144/0x184 > > [] acpi_ns_parse_table+0x48/0x68 > > [] acpi_ns_load_table+0x4c/0xdc > > [] acpi_tb_load_namespace+0xe4/0x264 > > [] acpi_load_tables+0x48/0xc0 > > [] acpi_early_init+0x9c/0xd0 > > [] start_kernel+0x3b4/0x43c > > Code: b9008fb9 2a000318 36380054 32190318 (b94002c0) > > ---[ end trace c46ed37f9651c58e ]--- > > Kernel panic - not syncing: Fatal exception > > Rebooting in 10 seconds.. > > > > (diagnosis) > > * This fault is a data abort, alignment fault (ESR=0x96000021) > > during reading out ACPI table. > > * Initial ACPI tables are normally stored in system ram and marked as > > "ACPI Reclaim memory" by the firmware. > > * After the commit f56ab9a5b73c ("efi/arm: Don't mark ACPI reclaim > > memory as MEMBLOCK_NOMAP"), those regions are differently handled > > as they are "memblock-reserved", without NOMAP bit. > > * So they are now excluded from device tree's "usable-memory-range" > > which kexec-tools determines based on a current view of /proc/iomem. > > * When crash dump kernel boots up, it tries to accesses ACPI tables by > > mapping them with ioremap(), not ioremap_cache(), in acpi_os_ioremap() > > since they are no longer part of mapped system ram. > > * Given that ACPI accessor/helper functions are compiled in without > > unaligned access support (ACPI_MISALIGNMENT_NOT_SUPPORTED), > > any unaligned access to ACPI tables can cause a fatal panic. > > > > With this patch, acpi_os_ioremap() always honors memory attribute > > information provided by the firmware (EFI) and retaining cacheability > > allows the kernel safe access to ACPI tables. > > > > Please note that arm_enable_runtime_services() is now renamed to > > efi_enter_virtual_mode() due to the similarity to x86's. > > Just a rename?: and maps EFI memory map whether or not runtime service is enabled. > > drivers/firmware/efi/arm-runtime.c | 27 ++++++++++++--------------- > > > > > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > > index 32f465a80e4e..d53c95f4e1a9 100644 > > --- a/arch/arm64/include/asm/acpi.h > > +++ b/arch/arm64/include/asm/acpi.h > > @@ -29,18 +31,22 @@ > > > > /* Basic configuration for ACPI */ > > #ifdef CONFIG_ACPI > > +pgprot_t __acpi_get_mem_attribute(phys_addr_t addr); > > + > > /* ACPI table mapping after acpi_permanent_mmap is set */ > > static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys, > > acpi_size size) > > { > > + /* For normal memory we already have a cacheable mapping. */ > > + if (memblock_is_map_memory(phys)) > > + return (void __iomem *)__phys_to_virt(phys); > > > /* > > - * EFI's reserve_regions() call adds memory with the WB attribute > > - * to memblock via early_init_dt_add_memory_arch(). > > + * We should still honor the memory's attribute here because > > + * crash dump kernel possibly excludes some ACPI (reclaim) > > + * regions from memblock list. > > */ > > (Even without kdump we would still need this. Regions ACPI wants mapped may not > be covered by the linear map. In this case we need to use the attributes > firmware described in the UEFI memory map. Kdump exacerbates this by > artificially reducing the range of the linear map.) > > > > - if (!memblock_is_memory(phys)) > > - return ioremap(phys, size); > > - > > - return ioremap_cache(phys, size); > > + return __ioremap(phys, size, __acpi_get_mem_attribute(phys)); > > } > > > > > diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c > > index 5889cbea60b8..566ef0a9edb5 100644 > > --- a/drivers/firmware/efi/arm-runtime.c > > +++ b/drivers/firmware/efi/arm-runtime.c > > @@ -106,46 +106,43 @@ static bool __init efi_virtmap_init(void) > > * non-early mapping of the UEFI system table and virtual mappings for all > > * EFI_MEMORY_RUNTIME regions. > > */ > > -static int __init arm_enable_runtime_services(void) > > +void __init efi_enter_virtual_mode(void) > > { > > u64 mapsize; > > > > if (!efi_enabled(EFI_BOOT)) { > > pr_info("EFI services will not be available.\n"); > > - return 0; > > + return; > > + } > > + > > + mapsize = efi.memmap.desc_size * efi.memmap.nr_map; > > + > > + if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { > > + pr_err("Failed to remap EFI memory map\n"); > > + return; > > } > > > > if (efi_runtime_disabled()) { > > pr_info("EFI runtime services will be disabled.\n"); > > - return 0; > > + return; > > } > > > > if (efi_enabled(EFI_RUNTIME_SERVICES)) { > > pr_info("EFI runtime services access via paravirt.\n"); > > - return 0; > > + return; > > } > > > > pr_info("Remapping and enabling EFI services.\n"); > > > > - mapsize = efi.memmap.desc_size * efi.memmap.nr_map; > > - > > - if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { > > - pr_err("Failed to remap EFI memory map\n"); > > - return -ENOMEM; > > - } > > - > > if (!efi_virtmap_init()) { > > pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n"); > > - return -ENOMEM; > > + return; > > } > > > > /* Set up runtime services function pointers */ > > efi_native_runtime_setup(); > > set_bit(EFI_RUNTIME_SERVICES, &efi.flags); > > - > > - return 0; > > } > > Please have the drivers/firmware/efi/arm-runtime.c changes in a separate patch > (maybe combine it with patch 3). The 'efi/arm: ' prefix is more likely to catch > the maintainers attention. > > I think this is what Ard meant by: > | Could you please move the changes to this file and init/main.c into a > | separate patch? > > https://patchwork.kernel.org/patch/10361761/ > > > > -early_initcall(arm_enable_runtime_services); > > With just this patch, surely nothing ever calls arm_enable_runtime_services(), > and now acpi_os_ioremap() will return device memory for anything that isn't part > of the linear region. (This breaks RAS). Actually I noticed the issue. > This will make it difficult to bisect through for any RAS or > efi-runtime-services issue. Its easily fixed: please put the efi+init changes in > a patch before the acpi_os_ioremap() changes. I was reluctant to put different part of code changes into one. But if nobody cares, I will do so in three patches. * change arm_enable_runtime_services() with renaming * move this function earlier in start_kernel() * modify acpi_os_ioremap() Thanks, -Takahiro AKASHI > Otherwise, looks good to me! > > > Thanks, > > James From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pf0-x241.google.com ([2607:f8b0:400e:c00::241]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1fUntF-000225-Rf for kexec@lists.infradead.org; Mon, 18 Jun 2018 06:43:51 +0000 Received: by mail-pf0-x241.google.com with SMTP id a22-v6so7650850pfo.12 for ; Sun, 17 Jun 2018 23:43:37 -0700 (PDT) Date: Mon, 18 Jun 2018 15:44:14 +0900 From: AKASHI Takahiro Subject: Re: [PATCH 2/3] arm64: acpi,efi: fix alignment fault in accessing ACPI tables at kdump Message-ID: <20180618064413.GF23681@linaro.org> References: <20180615075623.13454-1-takahiro.akashi@linaro.org> <20180615075623.13454-3-takahiro.akashi@linaro.org> <026a4d23-ac91-ed35-d711-c55882242037@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <026a4d23-ac91-ed35-d711-c55882242037@arm.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: James Morse Cc: mark.rutland@arm.com, lorenzo.pieralisi@arm.com, graeme.gregory@linaro.org, al.stone@linaro.org, ard.biesheuvel@linaro.org, catalin.marinas@arm.com, bhsharma@redhat.com, tbaicar@codeaurora.org, will.deacon@arm.com, linux-kernel@vger.kernel.org, hanjun.guo@linaro.org, sudeep.holla@arm.com, akpm@linux-foundation.org, dyoung@redhat.com, kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org James, On Fri, Jun 15, 2018 at 05:30:08PM +0100, James Morse wrote: > Hi Akashi, > > On 15/06/18 08:56, AKASHI Takahiro wrote: > > This is a fix against the issue that crash dump kernel may hang up > > during booting, which can happen on any ACPI-based system with "ACPI > > Reclaim Memory." > > > > (kernel messages after panic kicked off kdump) > > (snip...) > > Bye! > > (snip...) > > ACPI: Core revision 20170728 > > pud=000000002e7d0003, *pmd=000000002e7c0003, *pte=00e8000039710707 > > Internal error: Oops: 96000021 [#1] SMP > > Modules linked in: > > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.0-rc6 #1 > > task: ffff000008d05180 task.stack: ffff000008cc0000 > > PC is at acpi_ns_lookup+0x25c/0x3c0 > > LR is at acpi_ds_load1_begin_op+0xa4/0x294 > > (snip...) > > Process swapper/0 (pid: 0, stack limit = 0xffff000008cc0000) > > Call trace: > > (snip...) > > [] acpi_ns_lookup+0x25c/0x3c0 > > [] acpi_ds_load1_begin_op+0xa4/0x294 > > [] acpi_ps_build_named_op+0xc4/0x198 > > [] acpi_ps_create_op+0x14c/0x270 > > [] acpi_ps_parse_loop+0x188/0x5c8 > > [] acpi_ps_parse_aml+0xb0/0x2b8 > > [] acpi_ns_one_complete_parse+0x144/0x184 > > [] acpi_ns_parse_table+0x48/0x68 > > [] acpi_ns_load_table+0x4c/0xdc > > [] acpi_tb_load_namespace+0xe4/0x264 > > [] acpi_load_tables+0x48/0xc0 > > [] acpi_early_init+0x9c/0xd0 > > [] start_kernel+0x3b4/0x43c > > Code: b9008fb9 2a000318 36380054 32190318 (b94002c0) > > ---[ end trace c46ed37f9651c58e ]--- > > Kernel panic - not syncing: Fatal exception > > Rebooting in 10 seconds.. > > > > (diagnosis) > > * This fault is a data abort, alignment fault (ESR=0x96000021) > > during reading out ACPI table. > > * Initial ACPI tables are normally stored in system ram and marked as > > "ACPI Reclaim memory" by the firmware. > > * After the commit f56ab9a5b73c ("efi/arm: Don't mark ACPI reclaim > > memory as MEMBLOCK_NOMAP"), those regions are differently handled > > as they are "memblock-reserved", without NOMAP bit. > > * So they are now excluded from device tree's "usable-memory-range" > > which kexec-tools determines based on a current view of /proc/iomem. > > * When crash dump kernel boots up, it tries to accesses ACPI tables by > > mapping them with ioremap(), not ioremap_cache(), in acpi_os_ioremap() > > since they are no longer part of mapped system ram. > > * Given that ACPI accessor/helper functions are compiled in without > > unaligned access support (ACPI_MISALIGNMENT_NOT_SUPPORTED), > > any unaligned access to ACPI tables can cause a fatal panic. > > > > With this patch, acpi_os_ioremap() always honors memory attribute > > information provided by the firmware (EFI) and retaining cacheability > > allows the kernel safe access to ACPI tables. > > > > Please note that arm_enable_runtime_services() is now renamed to > > efi_enter_virtual_mode() due to the similarity to x86's. > > Just a rename?: and maps EFI memory map whether or not runtime service is enabled. > > drivers/firmware/efi/arm-runtime.c | 27 ++++++++++++--------------- > > > > > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > > index 32f465a80e4e..d53c95f4e1a9 100644 > > --- a/arch/arm64/include/asm/acpi.h > > +++ b/arch/arm64/include/asm/acpi.h > > @@ -29,18 +31,22 @@ > > > > /* Basic configuration for ACPI */ > > #ifdef CONFIG_ACPI > > +pgprot_t __acpi_get_mem_attribute(phys_addr_t addr); > > + > > /* ACPI table mapping after acpi_permanent_mmap is set */ > > static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys, > > acpi_size size) > > { > > + /* For normal memory we already have a cacheable mapping. */ > > + if (memblock_is_map_memory(phys)) > > + return (void __iomem *)__phys_to_virt(phys); > > > /* > > - * EFI's reserve_regions() call adds memory with the WB attribute > > - * to memblock via early_init_dt_add_memory_arch(). > > + * We should still honor the memory's attribute here because > > + * crash dump kernel possibly excludes some ACPI (reclaim) > > + * regions from memblock list. > > */ > > (Even without kdump we would still need this. Regions ACPI wants mapped may not > be covered by the linear map. In this case we need to use the attributes > firmware described in the UEFI memory map. Kdump exacerbates this by > artificially reducing the range of the linear map.) > > > > - if (!memblock_is_memory(phys)) > > - return ioremap(phys, size); > > - > > - return ioremap_cache(phys, size); > > + return __ioremap(phys, size, __acpi_get_mem_attribute(phys)); > > } > > > > > diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c > > index 5889cbea60b8..566ef0a9edb5 100644 > > --- a/drivers/firmware/efi/arm-runtime.c > > +++ b/drivers/firmware/efi/arm-runtime.c > > @@ -106,46 +106,43 @@ static bool __init efi_virtmap_init(void) > > * non-early mapping of the UEFI system table and virtual mappings for all > > * EFI_MEMORY_RUNTIME regions. > > */ > > -static int __init arm_enable_runtime_services(void) > > +void __init efi_enter_virtual_mode(void) > > { > > u64 mapsize; > > > > if (!efi_enabled(EFI_BOOT)) { > > pr_info("EFI services will not be available.\n"); > > - return 0; > > + return; > > + } > > + > > + mapsize = efi.memmap.desc_size * efi.memmap.nr_map; > > + > > + if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { > > + pr_err("Failed to remap EFI memory map\n"); > > + return; > > } > > > > if (efi_runtime_disabled()) { > > pr_info("EFI runtime services will be disabled.\n"); > > - return 0; > > + return; > > } > > > > if (efi_enabled(EFI_RUNTIME_SERVICES)) { > > pr_info("EFI runtime services access via paravirt.\n"); > > - return 0; > > + return; > > } > > > > pr_info("Remapping and enabling EFI services.\n"); > > > > - mapsize = efi.memmap.desc_size * efi.memmap.nr_map; > > - > > - if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) { > > - pr_err("Failed to remap EFI memory map\n"); > > - return -ENOMEM; > > - } > > - > > if (!efi_virtmap_init()) { > > pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n"); > > - return -ENOMEM; > > + return; > > } > > > > /* Set up runtime services function pointers */ > > efi_native_runtime_setup(); > > set_bit(EFI_RUNTIME_SERVICES, &efi.flags); > > - > > - return 0; > > } > > Please have the drivers/firmware/efi/arm-runtime.c changes in a separate patch > (maybe combine it with patch 3). The 'efi/arm: ' prefix is more likely to catch > the maintainers attention. > > I think this is what Ard meant by: > | Could you please move the changes to this file and init/main.c into a > | separate patch? > > https://patchwork.kernel.org/patch/10361761/ > > > > -early_initcall(arm_enable_runtime_services); > > With just this patch, surely nothing ever calls arm_enable_runtime_services(), > and now acpi_os_ioremap() will return device memory for anything that isn't part > of the linear region. (This breaks RAS). Actually I noticed the issue. > This will make it difficult to bisect through for any RAS or > efi-runtime-services issue. Its easily fixed: please put the efi+init changes in > a patch before the acpi_os_ioremap() changes. I was reluctant to put different part of code changes into one. But if nobody cares, I will do so in three patches. * change arm_enable_runtime_services() with renaming * move this function earlier in start_kernel() * modify acpi_os_ioremap() Thanks, -Takahiro AKASHI > Otherwise, looks good to me! > > > Thanks, > > James _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec