[PATCH 0/3] add LPAE support for kexec and kernel

[PATCH 0/3] add LPAE support for kexec and kernel

[Liu Hua]

The patch series introduce LPAE support for user space
utility kexec(the last) and ARM linux kernel(the others).

I have tested the patch series in armA15 platform which have
more than 4G memory.

Liu Hua (2):
  ARM : kdump : Add LPAE support
  ARM : kdump : add arch_crash_save_vmcoreinfo

 arch/arm/include/asm/elf.h      |  4 +++-
 arch/arm/kernel/elf.c           | 33 +++++++++++++++++++++++++++++++++
 arch/arm/kernel/machine_kexec.c |  7 +++++++
 3 files changed, 43 insertions(+), 1 deletion(-)

Liu Hua (1):
  kexec: ARM: add LPAE support

 kexec/arch/arm/crashdump-arm.c | 23 ++++++++++++++++++++---
 kexec/kexec-iomem.c            |  8 ++++----
 kexec/kexec.h                  |  4 ++--
 3 files changed, 26 insertions(+), 9 deletions(-)

-- 
1.9.0

[PATCH 1/3] ARM : kdump : Add LPAE support

[Liu Hua]

With CONFIG_LPAE=y, memory in 32-bit ARM systems can exceed
4G. So if we use kdump in such systems. The capture kernel
should parse 64-bit elf header(parse_crash_elf64_headers).

And this process can not pass because ARM linux does not
supply related check function.

This patch adds check functions related of elf64 header.

Signed-off-by: Liu Hua <sdu.liu@huawei.com>
To: Russell King <linux@arm.linux.org.uk>
Cc: Dan Aloni <alonid@stratoscale.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: <linux-kernel@vger.kernel.org>
Cc: <kexec@lists.infradead.org>
---
 arch/arm/include/asm/elf.h |  5 ++++-
 arch/arm/kernel/elf.c      | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h
index f4b46d3..6e02a6d 100644
--- a/arch/arm/include/asm/elf.h
+++ b/arch/arm/include/asm/elf.h
@@ -90,14 +90,17 @@ typedef struct user_fp elf_fpregset_t;
 extern char elf_platform[];
 
 struct elf32_hdr;
+struct elf64_hdr;
 
 /*
  * This is used to ensure we don't load something for the wrong architecture.
  */
 extern int elf_check_arch(const struct elf32_hdr *);
+extern int elf_check_arch_64(const struct elf64_hdr *);
 #define elf_check_arch elf_check_arch
 
-#define vmcore_elf64_check_arch(x) (0)
+#define vmcore_elf64_check_arch(x) (elf_check_arch_64(x) || \
+				vmcore_elf_check_arch_cross(x))
 
 extern int arm_elf_read_implies_exec(const struct elf32_hdr *, int);
 #define elf_read_implies_exec(ex,stk) arm_elf_read_implies_exec(&(ex), stk)
diff --git a/arch/arm/kernel/elf.c b/arch/arm/kernel/elf.c
index d0d1e83..452086a 100644
--- a/arch/arm/kernel/elf.c
+++ b/arch/arm/kernel/elf.c
@@ -38,6 +38,39 @@ int elf_check_arch(const struct elf32_hdr *x)
 }
 EXPORT_SYMBOL(elf_check_arch);
 
+int elf_check_arch_64(const struct elf64_hdr *x)
+{
+	unsigned int eflags;
+
+	/* Make sure it's an ARM executable */
+	if (x->e_machine != EM_ARM)
+		return 0;
+
+	/* Make sure the entry address is reasonable */
+	if (x->e_entry & 1) {
+		if (!(elf_hwcap & HWCAP_THUMB))
+			return 0;
+	} else if (x->e_entry & 3)
+		return 0;
+
+	eflags = x->e_flags;
+	if ((eflags & EF_ARM_EABI_MASK) == EF_ARM_EABI_UNKNOWN) {
+		unsigned int flt_fmt;
+
+		/* APCS26 is only allowed if the CPU supports it */
+		if ((eflags & EF_ARM_APCS_26) && !(elf_hwcap & HWCAP_26BIT))
+			return 0;
+
+		flt_fmt = eflags & (EF_ARM_VFP_FLOAT | EF_ARM_SOFT_FLOAT);
+
+		/* VFP requires the supporting code */
+		if (flt_fmt == EF_ARM_VFP_FLOAT && !(elf_hwcap & HWCAP_VFP))
+			return 0;
+	}
+	return 1;
+}
+EXPORT_SYMBOL(elf_check_arch_64);
+
 void elf_set_personality(const struct elf32_hdr *x)
 {
 	unsigned int eflags = x->e_flags;
-- 
1.9.0

[PATCH 2/3] ARM : kdump : add arch_crash_save_vmcoreinfo

[Liu Hua]

For vmcore generated by LPAE enabled kernel, user space
utility such as crash needs additional infomation to
parse.

So this patch add arch_crash_save_vmcoreinfo as what PAE enabled
i386 linux does.

Signed-off-by: Liu Hua <sdu.liu@huawei.com>
To: Russell King <linux@arm.linux.org.uk>
Cc: Stephen Warren <swarren@nvidia.com> 
Cc: Will Deacon <will.deacon@arm.com>
Cc: Vijaya Kumar K <vijay.kilari@gmail.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: <linux-kernel@vger.kernel.org>
Cc: <kexec@lists.infradead.org>
---
 arch/arm/kernel/machine_kexec.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
index f0d180d..8cf0996 100644
--- a/arch/arm/kernel/machine_kexec.c
+++ b/arch/arm/kernel/machine_kexec.c
@@ -184,3 +184,10 @@ void machine_kexec(struct kimage *image)
 
 	soft_restart(reboot_entry_phys);
 }
+
+void arch_crash_save_vmcoreinfo(void)
+{
+#ifdef CONFIG_ARM_LPAE
+	VMCOREINFO_CONFIG(ARM_LPAE);
+#endif
+}
-- 
1.9.0

[PATCH 3/3] kexec : ARM : add LPAE support

[Liu Hua]

For 32-bit ARM systems with CONFIG_ARM_LPAE=y, when kexec utility
loads the crash kernel. 32-bit elf header is not enough if the
physical address exceeds 4G.

This patch check whether the largest physical address of the system
exceeds 4G. If so, kexec creates 64-bit elf header.Otherwise it
creates 32-bit elf header.

Signed-off-by: Liu Hua <sdu.liu@huawei.com>
To: Simon Horman <horms@verge.net.au>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: <kexec@lists.infradead.org>
Cc: <linux-kernel@vger.kernel.org>
Cc: <linux-arm-kernel@lists.infradead.org>
---
 kexec/arch/arm/crashdump-arm.c | 23 ++++++++++++++++++++---
 kexec/kexec-iomem.c            |  8 ++++----
 kexec/kexec.h                  |  4 ++--
 3 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/kexec/arch/arm/crashdump-arm.c b/kexec/arch/arm/crashdump-arm.c
index 0cd6935..d1133cd 100644
--- a/kexec/arch/arm/crashdump-arm.c
+++ b/kexec/arch/arm/crashdump-arm.c
@@ -20,6 +20,7 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
+#include <limits.h>
 #include <elf.h>
 #include <errno.h>
 #include <stdio.h>
@@ -75,8 +76,8 @@ unsigned long phys_offset;
  * regions is placed in @crash_memory_nr_ranges.
  */
 static int crash_range_callback(void *UNUSED(data), int UNUSED(nr),
-				char *str, unsigned long base,
-				unsigned long length)
+				char *str, unsigned long long base,
+				unsigned long long length)
 {
 	struct memory_range *range;
 
@@ -276,6 +277,7 @@ int load_crashdump_segments(struct kexec_info *info, char *mod_cmdline)
 	unsigned long bufsz;
 	void *buf;
 	int err;
+	int last_ranges;
 
 	/*
 	 * First fetch all the memory (RAM) ranges that we are going to pass to
@@ -292,10 +294,25 @@ int load_crashdump_segments(struct kexec_info *info, char *mod_cmdline)
 	phys_offset = usablemem_rgns.ranges->start;
 	dbgprintf("phys_offset: %#lx\n", phys_offset);
 
-	err = crash_create_elf32_headers(info, &elf_info,
+	last_ranges = usablemem_rgns.size - 1;
+	if (last_ranges < 0)
+		last_ranges = 0;
+
+	if (crash_memory_ranges[last_ranges].end > ULONG_MAX) {
+
+		/* for support arm LPAE and arm64 */
+		elf_info.class = ELFCLASS64;
+
+		err = crash_create_elf64_headers(info, &elf_info,
 					 usablemem_rgns.ranges,
 					 usablemem_rgns.size, &buf, &bufsz,
 					 ELF_CORE_HEADER_ALIGN);
+	} else {
+		err = crash_create_elf32_headers(info, &elf_info,
+					 usablemem_rgns.ranges,
+					 usablemem_rgns.size, &buf, &bufsz,
+					 ELF_CORE_HEADER_ALIGN);
+	}
 	if (err)
 		return err;
 
diff --git a/kexec/kexec-iomem.c b/kexec/kexec-iomem.c
index 0396713..485a2e8 100644
--- a/kexec/kexec-iomem.c
+++ b/kexec/kexec-iomem.c
@@ -26,8 +26,8 @@ int kexec_iomem_for_each_line(char *match,
 			      int (*callback)(void *data,
 					      int nr,
 					      char *str,
-					      unsigned long base,
-					      unsigned long length),
+					      unsigned long long base,
+					      unsigned long long length),
 			      void *data)
 {
 	const char *iomem = proc_iomem();
@@ -65,8 +65,8 @@ int kexec_iomem_for_each_line(char *match,
 
 static int kexec_iomem_single_callback(void *data, int nr,
 				       char *UNUSED(str),
-				       unsigned long base,
-				       unsigned long length)
+				       unsigned long long base,
+				       unsigned long long length)
 {
 	struct memory_range *range = data;
 
diff --git a/kexec/kexec.h b/kexec/kexec.h
index 2bd6e96..ecc4681 100644
--- a/kexec/kexec.h
+++ b/kexec/kexec.h
@@ -279,8 +279,8 @@ int kexec_iomem_for_each_line(char *match,
 			      int (*callback)(void *data,
 					      int nr,
 					      char *str,
-					      unsigned long base,
-					      unsigned long length),
+					      unsigned long long base,
+					      unsigned long long length),
 			      void *data);
 int parse_iomem_single(char *str, uint64_t *start, uint64_t *end);
 const char * proc_iomem(void);
-- 
1.9.0

[PATCH 2/3] ARM : kdump : add arch_crash_save_vmcoreinfo

[Will Deacon]

On Thu, Mar 27, 2014 at 08:00:39AM +0000, Liu Hua wrote:
> For vmcore generated by LPAE enabled kernel, user space
> utility such as crash needs additional infomation to
> parse.
> 
> So this patch add arch_crash_save_vmcoreinfo as what PAE enabled
> i386 linux does.

Looks sensible to me:

  Reviewed-by: Will Deacon <will.deacon@arm.com>

Will

> Signed-off-by: Liu Hua <sdu.liu@huawei.com>
> To: Russell King <linux@arm.linux.org.uk>
> Cc: Stephen Warren <swarren@nvidia.com> 
> Cc: Will Deacon <will.deacon@arm.com>
> Cc: Vijaya Kumar K <vijay.kilari@gmail.com>
> Cc: <linux-arm-kernel@lists.infradead.org>
> Cc: <linux-kernel@vger.kernel.org>
> Cc: <kexec@lists.infradead.org>
> ---
>  arch/arm/kernel/machine_kexec.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
> index f0d180d..8cf0996 100644
> --- a/arch/arm/kernel/machine_kexec.c
> +++ b/arch/arm/kernel/machine_kexec.c
> @@ -184,3 +184,10 @@ void machine_kexec(struct kimage *image)
>  
>  	soft_restart(reboot_entry_phys);
>  }
> +
> +void arch_crash_save_vmcoreinfo(void)
> +{
> +#ifdef CONFIG_ARM_LPAE
> +	VMCOREINFO_CONFIG(ARM_LPAE);
> +#endif
> +}
> -- 
> 1.9.0
> 
> 

[PATCH 2/3] ARM : kdump : add arch_crash_save_vmcoreinfo

[Liu hua]

? 2014/4/14 19:37, Will Deacon ??:
> On Thu, Mar 27, 2014 at 08:00:39AM +0000, Liu Hua wrote:
>> For vmcore generated by LPAE enabled kernel, user space
>> utility such as crash needs additional infomation to
>> parse.
>>
>> So this patch add arch_crash_save_vmcoreinfo as what PAE enabled
>> i386 linux does.
> 
> Looks sensible to me:
> 
>   Reviewed-by: Will Deacon <will.deacon@arm.com>
> 
> Will

Hi Will,

Thanks to you reply. How about the first one of the patch
series named "[PATCH 1/3] ARM : kdump : Add LPAE support".

Now the ARM linux will simply return error when parse an
LPAE enabled kernel, becausethe commit 4b3bf7ae provide
zero vmcore_elf64_check_arch(). So if we want parse LPAE
enabled kernel, we need that one.

Thanks,
Liu Hua
> 
>> Signed-off-by: Liu Hua <sdu.liu@huawei.com>
>> To: Russell King <linux@arm.linux.org.uk>
>> Cc: Stephen Warren <swarren@nvidia.com> 
>> Cc: Will Deacon <will.deacon@arm.com>
>> Cc: Vijaya Kumar K <vijay.kilari@gmail.com>
>> Cc: <linux-arm-kernel@lists.infradead.org>
>> Cc: <linux-kernel@vger.kernel.org>
>> Cc: <kexec@lists.infradead.org>
>> ---
>>  arch/arm/kernel/machine_kexec.c | 7 +++++++
>>  1 file changed, 7 insertions(+)
>>
>> diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
>> index f0d180d..8cf0996 100644
>> --- a/arch/arm/kernel/machine_kexec.c
>> +++ b/arch/arm/kernel/machine_kexec.c
>> @@ -184,3 +184,10 @@ void machine_kexec(struct kimage *image)
>>  
>>  	soft_restart(reboot_entry_phys);
>>  }
>> +
>> +void arch_crash_save_vmcoreinfo(void)
>> +{
>> +#ifdef CONFIG_ARM_LPAE
>> +	VMCOREINFO_CONFIG(ARM_LPAE);
>> +#endif
>> +}
>> -- 
>> 1.9.0
>>
>>
> 
> .
> 

[PATCH 2/3] ARM : kdump : add arch_crash_save_vmcoreinfo

[Will Deacon]

On Mon, Apr 14, 2014 at 01:41:34PM +0100, Liu hua wrote:
> ? 2014/4/14 19:37, Will Deacon ??:
> > On Thu, Mar 27, 2014 at 08:00:39AM +0000, Liu Hua wrote:
> >> For vmcore generated by LPAE enabled kernel, user space
> >> utility such as crash needs additional infomation to
> >> parse.
> >>
> >> So this patch add arch_crash_save_vmcoreinfo as what PAE enabled
> >> i386 linux does.
> > 
> > Looks sensible to me:
> > 
> >   Reviewed-by: Will Deacon <will.deacon@arm.com>
> > 
> > Will
> 
> Hi Will,
> 
> Thanks to you reply. How about the first one of the patch
> series named "[PATCH 1/3] ARM : kdump : Add LPAE support".

I don't think you CC'd me on that one, so I doubt I have it in my mailbox
anymore. If you've not had any feedback, perhaps you can resend the series
with me on CC next time?

Thanks,

Will