* [RESEND PATCH] arm64: acpi, efi: fix alignment fault in accessing ACPI tables at kdump
@ 2018-04-25 6:35 AKASHI Takahiro
2018-04-25 8:09 ` Ard Biesheuvel
0 siblings, 1 reply; 4+ messages in thread
From: AKASHI Takahiro @ 2018-04-25 6:35 UTC (permalink / raw)
To: linux-arm-kernel
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...)
[<ffff0000084a6764>] acpi_ns_lookup+0x25c/0x3c0
[<ffff00000849b4f8>] acpi_ds_load1_begin_op+0xa4/0x294
[<ffff0000084ad4ac>] acpi_ps_build_named_op+0xc4/0x198
[<ffff0000084ad6cc>] acpi_ps_create_op+0x14c/0x270
[<ffff0000084acfa8>] acpi_ps_parse_loop+0x188/0x5c8
[<ffff0000084ae048>] acpi_ps_parse_aml+0xb0/0x2b8
[<ffff0000084a8e10>] acpi_ns_one_complete_parse+0x144/0x184
[<ffff0000084a8e98>] acpi_ns_parse_table+0x48/0x68
[<ffff0000084a82cc>] acpi_ns_load_table+0x4c/0xdc
[<ffff0000084b32f8>] acpi_tb_load_namespace+0xe4/0x264
[<ffff000008baf9b4>] acpi_load_tables+0x48/0xc0
[<ffff000008badc20>] acpi_early_init+0x9c/0xd0
[<ffff000008b70d50>] 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 a memory attribute
provided by the firmware (efi). Hence retaining cacheability in said cases
allows the kernel safe access to ACPI tables.
Please note that arm_enable_runtime_services(), which is renamed to
efi_enter_virtual_mode() due to the similarity to x86's, is now called
earlier before acpi_early_init() since efi_mem_attributes() relies on
efi.memmap being mapped.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Suggested-by: James Morse <james.morse@arm.com>
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by and Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
---
arch/arm64/include/asm/acpi.h | 23 ++++++++++++++++-------
arch/arm64/kernel/acpi.c | 11 +++--------
drivers/firmware/efi/arm-runtime.c | 15 ++++++---------
init/main.c | 3 +++
4 files changed, 28 insertions(+), 24 deletions(-)
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
@@ -12,10 +12,12 @@
#ifndef _ASM_ACPI_H
#define _ASM_ACPI_H
+#include <linux/efi.h>
#include <linux/memblock.h>
#include <linux/psci.h>
#include <asm/cputype.h>
+#include <asm/io.h>
#include <asm/smp_plat.h>
#include <asm/tlbflush.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.
*/
- if (!memblock_is_memory(phys))
- return ioremap(phys, size);
-
- return ioremap_cache(phys, size);
+ return __ioremap(phys, size, __acpi_get_mem_attribute(phys));
}
#define acpi_os_ioremap acpi_os_ioremap
@@ -125,7 +131,10 @@ static inline const char *acpi_get_enable_method(int cpu)
* for compatibility.
*/
#define acpi_disable_cmcff 1
-pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr);
+static inline pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
+{
+ return __acpi_get_mem_attribute(addr);
+}
#endif /* CONFIG_ACPI_APEI */
#ifdef CONFIG_ACPI_NUMA
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 7b09487ff8fb..7880076c1cf0 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -18,6 +18,7 @@
#include <linux/acpi.h>
#include <linux/bootmem.h>
#include <linux/cpumask.h>
+# include <linux/efi.h>
#include <linux/efi-bgrt.h>
#include <linux/init.h>
#include <linux/irq.h>
@@ -29,12 +30,8 @@
#include <asm/cputype.h>
#include <asm/cpu_ops.h>
-#include <asm/smp_plat.h>
-
-#ifdef CONFIG_ACPI_APEI
-# include <linux/efi.h>
# include <asm/pgtable.h>
-#endif
+#include <asm/smp_plat.h>
int acpi_noirq = 1; /* skip ACPI IRQ initialization */
int acpi_disabled = 1;
@@ -239,8 +236,7 @@ void __init acpi_boot_table_init(void)
}
}
-#ifdef CONFIG_ACPI_APEI
-pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
+pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
{
/*
* According to "Table 8 Map: EFI memory types to AArch64 memory
@@ -261,4 +257,3 @@ pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
return __pgprot(PROT_NORMAL_NC);
return __pgprot(PROT_DEVICE_nGnRnE);
}
-#endif
diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
index 5889cbea60b8..1148ea5a0faa 100644
--- a/drivers/firmware/efi/arm-runtime.c
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -106,23 +106,23 @@ 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;
}
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");
@@ -131,21 +131,18 @@ static int __init arm_enable_runtime_services(void)
if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
pr_err("Failed to remap EFI memory map\n");
- return -ENOMEM;
+ return;
}
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;
}
-early_initcall(arm_enable_runtime_services);
void efi_virtmap_load(void)
{
diff --git a/init/main.c b/init/main.c
index b795aa341a3a..40d05b63960f 100644
--- a/init/main.c
+++ b/init/main.c
@@ -693,6 +693,9 @@ asmlinkage __visible void __init start_kernel(void)
debug_objects_mem_init();
setup_per_cpu_pageset();
numa_policy_init();
+ if (IS_ENABLED(CONFIG_EFI) &&
+ (IS_ENABLED(CONFIG_ARM64) || IS_ENABLED(CONFIG_ARM)))
+ efi_enter_virtual_mode();
acpi_early_init();
if (late_time_init)
late_time_init();
--
2.17.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [RESEND PATCH] arm64: acpi, efi: fix alignment fault in accessing ACPI tables at kdump
2018-04-25 6:35 [RESEND PATCH] arm64: acpi, efi: fix alignment fault in accessing ACPI tables at kdump AKASHI Takahiro
@ 2018-04-25 8:09 ` Ard Biesheuvel
2018-04-25 9:06 ` AKASHI Takahiro
0 siblings, 1 reply; 4+ messages in thread
From: Ard Biesheuvel @ 2018-04-25 8:09 UTC (permalink / raw)
To: linux-arm-kernel
On 25 April 2018 at 08:35, AKASHI Takahiro <takahiro.akashi@linaro.org> 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...)
> [<ffff0000084a6764>] acpi_ns_lookup+0x25c/0x3c0
> [<ffff00000849b4f8>] acpi_ds_load1_begin_op+0xa4/0x294
> [<ffff0000084ad4ac>] acpi_ps_build_named_op+0xc4/0x198
> [<ffff0000084ad6cc>] acpi_ps_create_op+0x14c/0x270
> [<ffff0000084acfa8>] acpi_ps_parse_loop+0x188/0x5c8
> [<ffff0000084ae048>] acpi_ps_parse_aml+0xb0/0x2b8
> [<ffff0000084a8e10>] acpi_ns_one_complete_parse+0x144/0x184
> [<ffff0000084a8e98>] acpi_ns_parse_table+0x48/0x68
> [<ffff0000084a82cc>] acpi_ns_load_table+0x4c/0xdc
> [<ffff0000084b32f8>] acpi_tb_load_namespace+0xe4/0x264
> [<ffff000008baf9b4>] acpi_load_tables+0x48/0xc0
> [<ffff000008badc20>] acpi_early_init+0x9c/0xd0
> [<ffff000008b70d50>] 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 a memory attribute
> provided by the firmware (efi). Hence retaining cacheability in said cases
> allows the kernel safe access to ACPI tables.
>
> Please note that arm_enable_runtime_services(), which is renamed to
> efi_enter_virtual_mode() due to the similarity to x86's, is now called
> earlier before acpi_early_init() since efi_mem_attributes() relies on
> efi.memmap being mapped.
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> Suggested-by: James Morse <james.morse@arm.com>
> Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Reported-by and Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
> ---
> arch/arm64/include/asm/acpi.h | 23 ++++++++++++++++-------
> arch/arm64/kernel/acpi.c | 11 +++--------
> drivers/firmware/efi/arm-runtime.c | 15 ++++++---------
> init/main.c | 3 +++
> 4 files changed, 28 insertions(+), 24 deletions(-)
>
> 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
> @@ -12,10 +12,12 @@
> #ifndef _ASM_ACPI_H
> #define _ASM_ACPI_H
>
> +#include <linux/efi.h>
> #include <linux/memblock.h>
> #include <linux/psci.h>
>
> #include <asm/cputype.h>
> +#include <asm/io.h>
> #include <asm/smp_plat.h>
> #include <asm/tlbflush.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.
> */
> - if (!memblock_is_memory(phys))
> - return ioremap(phys, size);
> -
> - return ioremap_cache(phys, size);
> + return __ioremap(phys, size, __acpi_get_mem_attribute(phys));
> }
> #define acpi_os_ioremap acpi_os_ioremap
>
> @@ -125,7 +131,10 @@ static inline const char *acpi_get_enable_method(int cpu)
> * for compatibility.
> */
> #define acpi_disable_cmcff 1
> -pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr);
> +static inline pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
> +{
> + return __acpi_get_mem_attribute(addr);
> +}
> #endif /* CONFIG_ACPI_APEI */
>
> #ifdef CONFIG_ACPI_NUMA
> diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
> index 7b09487ff8fb..7880076c1cf0 100644
> --- a/arch/arm64/kernel/acpi.c
> +++ b/arch/arm64/kernel/acpi.c
> @@ -18,6 +18,7 @@
> #include <linux/acpi.h>
> #include <linux/bootmem.h>
> #include <linux/cpumask.h>
> +# include <linux/efi.h>
Please drop the space after #
> #include <linux/efi-bgrt.h>
> #include <linux/init.h>
> #include <linux/irq.h>
> @@ -29,12 +30,8 @@
>
> #include <asm/cputype.h>
> #include <asm/cpu_ops.h>
> -#include <asm/smp_plat.h>
> -
> -#ifdef CONFIG_ACPI_APEI
> -# include <linux/efi.h>
> # include <asm/pgtable.h>
And here
> -#endif
> +#include <asm/smp_plat.h>
>
> int acpi_noirq = 1; /* skip ACPI IRQ initialization */
> int acpi_disabled = 1;
> @@ -239,8 +236,7 @@ void __init acpi_boot_table_init(void)
> }
> }
>
> -#ifdef CONFIG_ACPI_APEI
> -pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
> +pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
> {
> /*
> * According to "Table 8 Map: EFI memory types to AArch64 memory
> @@ -261,4 +257,3 @@ pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
> return __pgprot(PROT_NORMAL_NC);
> return __pgprot(PROT_DEVICE_nGnRnE);
> }
> -#endif
> diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
> index 5889cbea60b8..1148ea5a0faa 100644
> --- a/drivers/firmware/efi/arm-runtime.c
> +++ b/drivers/firmware/efi/arm-runtime.c
> @@ -106,23 +106,23 @@ 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;
> }
>
> if (efi_runtime_disabled()) {
> pr_info("EFI runtime services will be disabled.\n");
> - return 0;
> + return;
> }
>
This is a problem. If you are booting using efi=noruntime, the routine
exits early and never sets up the mapping for the EFI memory map.
So the efi_memmap_init_late() call should be moved before the
efi_runtime_disabled() check, everything else can stay as is afaict
Could you please move the changes to this file and init/main.c into a
separate patch?
> 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");
> @@ -131,21 +131,18 @@ static int __init arm_enable_runtime_services(void)
>
> if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
> pr_err("Failed to remap EFI memory map\n");
> - return -ENOMEM;
> + return;
> }
>
> 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;
> }
> -early_initcall(arm_enable_runtime_services);
>
> void efi_virtmap_load(void)
> {
> diff --git a/init/main.c b/init/main.c
> index b795aa341a3a..40d05b63960f 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -693,6 +693,9 @@ asmlinkage __visible void __init start_kernel(void)
> debug_objects_mem_init();
> setup_per_cpu_pageset();
> numa_policy_init();
> + if (IS_ENABLED(CONFIG_EFI) &&
> + (IS_ENABLED(CONFIG_ARM64) || IS_ENABLED(CONFIG_ARM)))
> + efi_enter_virtual_mode();
> acpi_early_init();
> if (late_time_init)
> late_time_init();
> --
> 2.17.0
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* [RESEND PATCH] arm64: acpi, efi: fix alignment fault in accessing ACPI tables at kdump
2018-04-25 8:09 ` Ard Biesheuvel
@ 2018-04-25 9:06 ` AKASHI Takahiro
2018-04-25 9:07 ` Ard Biesheuvel
0 siblings, 1 reply; 4+ messages in thread
From: AKASHI Takahiro @ 2018-04-25 9:06 UTC (permalink / raw)
To: linux-arm-kernel
Ard,
On Wed, Apr 25, 2018 at 10:09:26AM +0200, Ard Biesheuvel wrote:
> On 25 April 2018 at 08:35, AKASHI Takahiro <takahiro.akashi@linaro.org> 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...)
> > [<ffff0000084a6764>] acpi_ns_lookup+0x25c/0x3c0
> > [<ffff00000849b4f8>] acpi_ds_load1_begin_op+0xa4/0x294
> > [<ffff0000084ad4ac>] acpi_ps_build_named_op+0xc4/0x198
> > [<ffff0000084ad6cc>] acpi_ps_create_op+0x14c/0x270
> > [<ffff0000084acfa8>] acpi_ps_parse_loop+0x188/0x5c8
> > [<ffff0000084ae048>] acpi_ps_parse_aml+0xb0/0x2b8
> > [<ffff0000084a8e10>] acpi_ns_one_complete_parse+0x144/0x184
> > [<ffff0000084a8e98>] acpi_ns_parse_table+0x48/0x68
> > [<ffff0000084a82cc>] acpi_ns_load_table+0x4c/0xdc
> > [<ffff0000084b32f8>] acpi_tb_load_namespace+0xe4/0x264
> > [<ffff000008baf9b4>] acpi_load_tables+0x48/0xc0
> > [<ffff000008badc20>] acpi_early_init+0x9c/0xd0
> > [<ffff000008b70d50>] 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 a memory attribute
> > provided by the firmware (efi). Hence retaining cacheability in said cases
> > allows the kernel safe access to ACPI tables.
> >
> > Please note that arm_enable_runtime_services(), which is renamed to
> > efi_enter_virtual_mode() due to the similarity to x86's, is now called
> > earlier before acpi_early_init() since efi_mem_attributes() relies on
> > efi.memmap being mapped.
> >
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > Suggested-by: James Morse <james.morse@arm.com>
> > Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> > Reported-by and Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
> > ---
> > arch/arm64/include/asm/acpi.h | 23 ++++++++++++++++-------
> > arch/arm64/kernel/acpi.c | 11 +++--------
> > drivers/firmware/efi/arm-runtime.c | 15 ++++++---------
> > init/main.c | 3 +++
> > 4 files changed, 28 insertions(+), 24 deletions(-)
> >
> > 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
> > @@ -12,10 +12,12 @@
> > #ifndef _ASM_ACPI_H
> > #define _ASM_ACPI_H
> >
> > +#include <linux/efi.h>
> > #include <linux/memblock.h>
> > #include <linux/psci.h>
> >
> > #include <asm/cputype.h>
> > +#include <asm/io.h>
> > #include <asm/smp_plat.h>
> > #include <asm/tlbflush.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.
> > */
> > - if (!memblock_is_memory(phys))
> > - return ioremap(phys, size);
> > -
> > - return ioremap_cache(phys, size);
> > + return __ioremap(phys, size, __acpi_get_mem_attribute(phys));
> > }
> > #define acpi_os_ioremap acpi_os_ioremap
> >
> > @@ -125,7 +131,10 @@ static inline const char *acpi_get_enable_method(int cpu)
> > * for compatibility.
> > */
> > #define acpi_disable_cmcff 1
> > -pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr);
> > +static inline pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
> > +{
> > + return __acpi_get_mem_attribute(addr);
> > +}
> > #endif /* CONFIG_ACPI_APEI */
> >
> > #ifdef CONFIG_ACPI_NUMA
> > diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
> > index 7b09487ff8fb..7880076c1cf0 100644
> > --- a/arch/arm64/kernel/acpi.c
> > +++ b/arch/arm64/kernel/acpi.c
> > @@ -18,6 +18,7 @@
> > #include <linux/acpi.h>
> > #include <linux/bootmem.h>
> > #include <linux/cpumask.h>
> > +# include <linux/efi.h>
>
> Please drop the space after #
Oops, will fix.
> > #include <linux/efi-bgrt.h>
> > #include <linux/init.h>
> > #include <linux/irq.h>
> > @@ -29,12 +30,8 @@
> >
> > #include <asm/cputype.h>
> > #include <asm/cpu_ops.h>
> > -#include <asm/smp_plat.h>
> > -
> > -#ifdef CONFIG_ACPI_APEI
> > -# include <linux/efi.h>
> > # include <asm/pgtable.h>
>
> And here
Yes, but it's not my change ...
> > -#endif
> > +#include <asm/smp_plat.h>
> >
> > int acpi_noirq = 1; /* skip ACPI IRQ initialization */
> > int acpi_disabled = 1;
> > @@ -239,8 +236,7 @@ void __init acpi_boot_table_init(void)
> > }
> > }
> >
> > -#ifdef CONFIG_ACPI_APEI
> > -pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
> > +pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
> > {
> > /*
> > * According to "Table 8 Map: EFI memory types to AArch64 memory
> > @@ -261,4 +257,3 @@ pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
> > return __pgprot(PROT_NORMAL_NC);
> > return __pgprot(PROT_DEVICE_nGnRnE);
> > }
> > -#endif
> > diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
> > index 5889cbea60b8..1148ea5a0faa 100644
> > --- a/drivers/firmware/efi/arm-runtime.c
> > +++ b/drivers/firmware/efi/arm-runtime.c
> > @@ -106,23 +106,23 @@ 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;
> > }
> >
> > if (efi_runtime_disabled()) {
> > pr_info("EFI runtime services will be disabled.\n");
> > - return 0;
> > + return;
> > }
> >
>
> This is a problem. If you are booting using efi=noruntime, the routine
> exits early and never sets up the mapping for the EFI memory map.
> So the efi_memmap_init_late() call should be moved before the
> efi_runtime_disabled() check, everything else can stay as is afaict
>
> Could you please move the changes to this file and init/main.c into a
> separate patch?
Okay.
Thank you for your reviewing.
-Takahiro AKASHI
> > 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");
> > @@ -131,21 +131,18 @@ static int __init arm_enable_runtime_services(void)
> >
> > if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
> > pr_err("Failed to remap EFI memory map\n");
> > - return -ENOMEM;
> > + return;
> > }
> >
> > 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;
> > }
> > -early_initcall(arm_enable_runtime_services);
> >
> > void efi_virtmap_load(void)
> > {
> > diff --git a/init/main.c b/init/main.c
> > index b795aa341a3a..40d05b63960f 100644
> > --- a/init/main.c
> > +++ b/init/main.c
> > @@ -693,6 +693,9 @@ asmlinkage __visible void __init start_kernel(void)
> > debug_objects_mem_init();
> > setup_per_cpu_pageset();
> > numa_policy_init();
> > + if (IS_ENABLED(CONFIG_EFI) &&
> > + (IS_ENABLED(CONFIG_ARM64) || IS_ENABLED(CONFIG_ARM)))
> > + efi_enter_virtual_mode();
> > acpi_early_init();
> > if (late_time_init)
> > late_time_init();
> > --
> > 2.17.0
> >
^ permalink raw reply [flat|nested] 4+ messages in thread
* [RESEND PATCH] arm64: acpi, efi: fix alignment fault in accessing ACPI tables at kdump
2018-04-25 9:06 ` AKASHI Takahiro
@ 2018-04-25 9:07 ` Ard Biesheuvel
0 siblings, 0 replies; 4+ messages in thread
From: Ard Biesheuvel @ 2018-04-25 9:07 UTC (permalink / raw)
To: linux-arm-kernel
On 25 April 2018 at 11:06, AKASHI Takahiro <takahiro.akashi@linaro.org> wrote:
> Ard,
>
> On Wed, Apr 25, 2018 at 10:09:26AM +0200, Ard Biesheuvel wrote:
>> On 25 April 2018 at 08:35, AKASHI Takahiro <takahiro.akashi@linaro.org> 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...)
>> > [<ffff0000084a6764>] acpi_ns_lookup+0x25c/0x3c0
>> > [<ffff00000849b4f8>] acpi_ds_load1_begin_op+0xa4/0x294
>> > [<ffff0000084ad4ac>] acpi_ps_build_named_op+0xc4/0x198
>> > [<ffff0000084ad6cc>] acpi_ps_create_op+0x14c/0x270
>> > [<ffff0000084acfa8>] acpi_ps_parse_loop+0x188/0x5c8
>> > [<ffff0000084ae048>] acpi_ps_parse_aml+0xb0/0x2b8
>> > [<ffff0000084a8e10>] acpi_ns_one_complete_parse+0x144/0x184
>> > [<ffff0000084a8e98>] acpi_ns_parse_table+0x48/0x68
>> > [<ffff0000084a82cc>] acpi_ns_load_table+0x4c/0xdc
>> > [<ffff0000084b32f8>] acpi_tb_load_namespace+0xe4/0x264
>> > [<ffff000008baf9b4>] acpi_load_tables+0x48/0xc0
>> > [<ffff000008badc20>] acpi_early_init+0x9c/0xd0
>> > [<ffff000008b70d50>] 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 a memory attribute
>> > provided by the firmware (efi). Hence retaining cacheability in said cases
>> > allows the kernel safe access to ACPI tables.
>> >
>> > Please note that arm_enable_runtime_services(), which is renamed to
>> > efi_enter_virtual_mode() due to the similarity to x86's, is now called
>> > earlier before acpi_early_init() since efi_mem_attributes() relies on
>> > efi.memmap being mapped.
>> >
>> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
>> > Suggested-by: James Morse <james.morse@arm.com>
>> > Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>> > Reported-by and Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
>> > ---
>> > arch/arm64/include/asm/acpi.h | 23 ++++++++++++++++-------
>> > arch/arm64/kernel/acpi.c | 11 +++--------
>> > drivers/firmware/efi/arm-runtime.c | 15 ++++++---------
>> > init/main.c | 3 +++
>> > 4 files changed, 28 insertions(+), 24 deletions(-)
>> >
>> > 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
>> > @@ -12,10 +12,12 @@
>> > #ifndef _ASM_ACPI_H
>> > #define _ASM_ACPI_H
>> >
>> > +#include <linux/efi.h>
>> > #include <linux/memblock.h>
>> > #include <linux/psci.h>
>> >
>> > #include <asm/cputype.h>
>> > +#include <asm/io.h>
>> > #include <asm/smp_plat.h>
>> > #include <asm/tlbflush.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.
>> > */
>> > - if (!memblock_is_memory(phys))
>> > - return ioremap(phys, size);
>> > -
>> > - return ioremap_cache(phys, size);
>> > + return __ioremap(phys, size, __acpi_get_mem_attribute(phys));
>> > }
>> > #define acpi_os_ioremap acpi_os_ioremap
>> >
>> > @@ -125,7 +131,10 @@ static inline const char *acpi_get_enable_method(int cpu)
>> > * for compatibility.
>> > */
>> > #define acpi_disable_cmcff 1
>> > -pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr);
>> > +static inline pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
>> > +{
>> > + return __acpi_get_mem_attribute(addr);
>> > +}
>> > #endif /* CONFIG_ACPI_APEI */
>> >
>> > #ifdef CONFIG_ACPI_NUMA
>> > diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
>> > index 7b09487ff8fb..7880076c1cf0 100644
>> > --- a/arch/arm64/kernel/acpi.c
>> > +++ b/arch/arm64/kernel/acpi.c
>> > @@ -18,6 +18,7 @@
>> > #include <linux/acpi.h>
>> > #include <linux/bootmem.h>
>> > #include <linux/cpumask.h>
>> > +# include <linux/efi.h>
>>
>> Please drop the space after #
>
> Oops, will fix.
>
>> > #include <linux/efi-bgrt.h>
>> > #include <linux/init.h>
>> > #include <linux/irq.h>
>> > @@ -29,12 +30,8 @@
>> >
>> > #include <asm/cputype.h>
>> > #include <asm/cpu_ops.h>
>> > -#include <asm/smp_plat.h>
>> > -
>> > -#ifdef CONFIG_ACPI_APEI
>> > -# include <linux/efi.h>
>> > # include <asm/pgtable.h>
>>
>> And here
>
> Yes, but it's not my change ...
>
The space is there because of the #ifdef, which you remove ...
>> > -#endif
>> > +#include <asm/smp_plat.h>
>> >
>> > int acpi_noirq = 1; /* skip ACPI IRQ initialization */
>> > int acpi_disabled = 1;
>> > @@ -239,8 +236,7 @@ void __init acpi_boot_table_init(void)
>> > }
>> > }
>> >
>> > -#ifdef CONFIG_ACPI_APEI
>> > -pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
>> > +pgprot_t __acpi_get_mem_attribute(phys_addr_t addr)
>> > {
>> > /*
>> > * According to "Table 8 Map: EFI memory types to AArch64 memory
>> > @@ -261,4 +257,3 @@ pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
>> > return __pgprot(PROT_NORMAL_NC);
>> > return __pgprot(PROT_DEVICE_nGnRnE);
>> > }
>> > -#endif
>> > diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
>> > index 5889cbea60b8..1148ea5a0faa 100644
>> > --- a/drivers/firmware/efi/arm-runtime.c
>> > +++ b/drivers/firmware/efi/arm-runtime.c
>> > @@ -106,23 +106,23 @@ 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;
>> > }
>> >
>> > if (efi_runtime_disabled()) {
>> > pr_info("EFI runtime services will be disabled.\n");
>> > - return 0;
>> > + return;
>> > }
>> >
>>
>> This is a problem. If you are booting using efi=noruntime, the routine
>> exits early and never sets up the mapping for the EFI memory map.
>> So the efi_memmap_init_late() call should be moved before the
>> efi_runtime_disabled() check, everything else can stay as is afaict
>>
>> Could you please move the changes to this file and init/main.c into a
>> separate patch?
>
> Okay.
>
> Thank you for your reviewing.
>
> -Takahiro AKASHI
>
>
>> > 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");
>> > @@ -131,21 +131,18 @@ static int __init arm_enable_runtime_services(void)
>> >
>> > if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
>> > pr_err("Failed to remap EFI memory map\n");
>> > - return -ENOMEM;
>> > + return;
>> > }
>> >
>> > 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;
>> > }
>> > -early_initcall(arm_enable_runtime_services);
>> >
>> > void efi_virtmap_load(void)
>> > {
>> > diff --git a/init/main.c b/init/main.c
>> > index b795aa341a3a..40d05b63960f 100644
>> > --- a/init/main.c
>> > +++ b/init/main.c
>> > @@ -693,6 +693,9 @@ asmlinkage __visible void __init start_kernel(void)
>> > debug_objects_mem_init();
>> > setup_per_cpu_pageset();
>> > numa_policy_init();
>> > + if (IS_ENABLED(CONFIG_EFI) &&
>> > + (IS_ENABLED(CONFIG_ARM64) || IS_ENABLED(CONFIG_ARM)))
>> > + efi_enter_virtual_mode();
>> > acpi_early_init();
>> > if (late_time_init)
>> > late_time_init();
>> > --
>> > 2.17.0
>> >
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2018-04-25 9:07 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2018-04-25 6:35 [RESEND PATCH] arm64: acpi, efi: fix alignment fault in accessing ACPI tables at kdump AKASHI Takahiro
2018-04-25 8:09 ` Ard Biesheuvel
2018-04-25 9:06 ` AKASHI Takahiro
2018-04-25 9:07 ` Ard Biesheuvel
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