[PATCH 0/5] mm: Stop alaising VM_FAULT_HINDEX_MASK in arch code

[PATCH 0/5] mm: Stop alaising VM_FAULT_HINDEX_MASK in arch code

[Palmer Dabbelt]

When reviewing
<https://lore.kernel.org/r/20221029084715.3669204-1-tongtiangen@huawei.com>
I noticed that the arch-specific VM_FAULT flags used by arm and s390
alias with VM_FAULT_HINDEX_MASK.  I'm not sure if it's possible to
manifest this as a bug, but it certainly seems fragile.

The RISC-V patch is on top of the linked patch above, which isn't in any
proper tree yet.  Everything else should apply to 6.1-rc1, but I'm in no
particular rush to get that cleanup in so rush on my end for 6.2.  That
said I figured it would be easier to send along this now, just in case
someone who knows the MM code better thinks it can manifest as a bug.

[PATCH 0/5] mm: Stop alaising VM_FAULT_HINDEX_MASK in arch code

[Palmer Dabbelt]

When reviewing
<https://lore.kernel.org/r/20221029084715.3669204-1-tongtiangen@huawei.com>
I noticed that the arch-specific VM_FAULT flags used by arm and s390
alias with VM_FAULT_HINDEX_MASK.  I'm not sure if it's possible to
manifest this as a bug, but it certainly seems fragile.

The RISC-V patch is on top of the linked patch above, which isn't in any
proper tree yet.  Everything else should apply to 6.1-rc1, but I'm in no
particular rush to get that cleanup in so rush on my end for 6.2.  That
said I figured it would be easier to send along this now, just in case
someone who knows the MM code better thinks it can manifest as a bug.


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

[PATCH 0/5] mm: Stop alaising VM_FAULT_HINDEX_MASK in arch code

[Palmer Dabbelt]

When reviewing
<https://lore.kernel.org/r/20221029084715.3669204-1-tongtiangen@huawei.com>
I noticed that the arch-specific VM_FAULT flags used by arm and s390
alias with VM_FAULT_HINDEX_MASK.  I'm not sure if it's possible to
manifest this as a bug, but it certainly seems fragile.

The RISC-V patch is on top of the linked patch above, which isn't in any
proper tree yet.  Everything else should apply to 6.1-rc1, but I'm in no
particular rush to get that cleanup in so rush on my end for 6.2.  That
said I figured it would be easier to send along this now, just in case
someone who knows the MM code better thinks it can manifest as a bug.


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 1/5] mm: Add a leading 0 to the VM_FAULT_* types

[Palmer Dabbelt]

The next patch will add enough codes to need another character, this
adds the 0 to all the existing codes to keep alignment.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 include/linux/mm_types.h | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 500e536796ca..758eb70829cb 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -862,24 +862,24 @@ typedef __bitwise unsigned int vm_fault_t;
  *				in DAX)
  * @VM_FAULT_COMPLETED:		->fault completed, meanwhile mmap lock released
  * @VM_FAULT_HINDEX_MASK:	mask HINDEX value
- *
+ * @VM_FAULT_ARCH_*:		Architecture-specific VM fault codes.
  */
 enum vm_fault_reason {
-	VM_FAULT_OOM            = (__force vm_fault_t)0x000001,
-	VM_FAULT_SIGBUS         = (__force vm_fault_t)0x000002,
-	VM_FAULT_MAJOR          = (__force vm_fault_t)0x000004,
-	VM_FAULT_WRITE          = (__force vm_fault_t)0x000008,
-	VM_FAULT_HWPOISON       = (__force vm_fault_t)0x000010,
-	VM_FAULT_HWPOISON_LARGE = (__force vm_fault_t)0x000020,
-	VM_FAULT_SIGSEGV        = (__force vm_fault_t)0x000040,
-	VM_FAULT_NOPAGE         = (__force vm_fault_t)0x000100,
-	VM_FAULT_LOCKED         = (__force vm_fault_t)0x000200,
-	VM_FAULT_RETRY          = (__force vm_fault_t)0x000400,
-	VM_FAULT_FALLBACK       = (__force vm_fault_t)0x000800,
-	VM_FAULT_DONE_COW       = (__force vm_fault_t)0x001000,
-	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x002000,
-	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x004000,
-	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x0f0000,
+	VM_FAULT_OOM            = (__force vm_fault_t)0x0000001,
+	VM_FAULT_SIGBUS         = (__force vm_fault_t)0x0000002,
+	VM_FAULT_MAJOR          = (__force vm_fault_t)0x0000004,
+	VM_FAULT_WRITE          = (__force vm_fault_t)0x0000008,
+	VM_FAULT_HWPOISON       = (__force vm_fault_t)0x0000010,
+	VM_FAULT_HWPOISON_LARGE = (__force vm_fault_t)0x0000020,
+	VM_FAULT_SIGSEGV        = (__force vm_fault_t)0x0000040,
+	VM_FAULT_NOPAGE         = (__force vm_fault_t)0x0000100,
+	VM_FAULT_LOCKED         = (__force vm_fault_t)0x0000200,
+	VM_FAULT_RETRY          = (__force vm_fault_t)0x0000400,
+	VM_FAULT_FALLBACK       = (__force vm_fault_t)0x0000800,
+	VM_FAULT_DONE_COW       = (__force vm_fault_t)0x0001000,
+	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x0002000,
+	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x0004000,
+	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x00f0000,
 };
 
 /* Encode hstate index for a hwpoisoned large page */
-- 
2.38.1

[PATCH 1/5] mm: Add a leading 0 to the VM_FAULT_* types

[Palmer Dabbelt]

The next patch will add enough codes to need another character, this
adds the 0 to all the existing codes to keep alignment.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 include/linux/mm_types.h | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 500e536796ca..758eb70829cb 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -862,24 +862,24 @@ typedef __bitwise unsigned int vm_fault_t;
  *				in DAX)
  * @VM_FAULT_COMPLETED:		->fault completed, meanwhile mmap lock released
  * @VM_FAULT_HINDEX_MASK:	mask HINDEX value
- *
+ * @VM_FAULT_ARCH_*:		Architecture-specific VM fault codes.
  */
 enum vm_fault_reason {
-	VM_FAULT_OOM            = (__force vm_fault_t)0x000001,
-	VM_FAULT_SIGBUS         = (__force vm_fault_t)0x000002,
-	VM_FAULT_MAJOR          = (__force vm_fault_t)0x000004,
-	VM_FAULT_WRITE          = (__force vm_fault_t)0x000008,
-	VM_FAULT_HWPOISON       = (__force vm_fault_t)0x000010,
-	VM_FAULT_HWPOISON_LARGE = (__force vm_fault_t)0x000020,
-	VM_FAULT_SIGSEGV        = (__force vm_fault_t)0x000040,
-	VM_FAULT_NOPAGE         = (__force vm_fault_t)0x000100,
-	VM_FAULT_LOCKED         = (__force vm_fault_t)0x000200,
-	VM_FAULT_RETRY          = (__force vm_fault_t)0x000400,
-	VM_FAULT_FALLBACK       = (__force vm_fault_t)0x000800,
-	VM_FAULT_DONE_COW       = (__force vm_fault_t)0x001000,
-	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x002000,
-	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x004000,
-	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x0f0000,
+	VM_FAULT_OOM            = (__force vm_fault_t)0x0000001,
+	VM_FAULT_SIGBUS         = (__force vm_fault_t)0x0000002,
+	VM_FAULT_MAJOR          = (__force vm_fault_t)0x0000004,
+	VM_FAULT_WRITE          = (__force vm_fault_t)0x0000008,
+	VM_FAULT_HWPOISON       = (__force vm_fault_t)0x0000010,
+	VM_FAULT_HWPOISON_LARGE = (__force vm_fault_t)0x0000020,
+	VM_FAULT_SIGSEGV        = (__force vm_fault_t)0x0000040,
+	VM_FAULT_NOPAGE         = (__force vm_fault_t)0x0000100,
+	VM_FAULT_LOCKED         = (__force vm_fault_t)0x0000200,
+	VM_FAULT_RETRY          = (__force vm_fault_t)0x0000400,
+	VM_FAULT_FALLBACK       = (__force vm_fault_t)0x0000800,
+	VM_FAULT_DONE_COW       = (__force vm_fault_t)0x0001000,
+	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x0002000,
+	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x0004000,
+	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x00f0000,
 };
 
 /* Encode hstate index for a hwpoisoned large page */
-- 
2.38.1


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

[PATCH 1/5] mm: Add a leading 0 to the VM_FAULT_* types

[Palmer Dabbelt]

The next patch will add enough codes to need another character, this
adds the 0 to all the existing codes to keep alignment.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 include/linux/mm_types.h | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 500e536796ca..758eb70829cb 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -862,24 +862,24 @@ typedef __bitwise unsigned int vm_fault_t;
  *				in DAX)
  * @VM_FAULT_COMPLETED:		->fault completed, meanwhile mmap lock released
  * @VM_FAULT_HINDEX_MASK:	mask HINDEX value
- *
+ * @VM_FAULT_ARCH_*:		Architecture-specific VM fault codes.
  */
 enum vm_fault_reason {
-	VM_FAULT_OOM            = (__force vm_fault_t)0x000001,
-	VM_FAULT_SIGBUS         = (__force vm_fault_t)0x000002,
-	VM_FAULT_MAJOR          = (__force vm_fault_t)0x000004,
-	VM_FAULT_WRITE          = (__force vm_fault_t)0x000008,
-	VM_FAULT_HWPOISON       = (__force vm_fault_t)0x000010,
-	VM_FAULT_HWPOISON_LARGE = (__force vm_fault_t)0x000020,
-	VM_FAULT_SIGSEGV        = (__force vm_fault_t)0x000040,
-	VM_FAULT_NOPAGE         = (__force vm_fault_t)0x000100,
-	VM_FAULT_LOCKED         = (__force vm_fault_t)0x000200,
-	VM_FAULT_RETRY          = (__force vm_fault_t)0x000400,
-	VM_FAULT_FALLBACK       = (__force vm_fault_t)0x000800,
-	VM_FAULT_DONE_COW       = (__force vm_fault_t)0x001000,
-	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x002000,
-	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x004000,
-	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x0f0000,
+	VM_FAULT_OOM            = (__force vm_fault_t)0x0000001,
+	VM_FAULT_SIGBUS         = (__force vm_fault_t)0x0000002,
+	VM_FAULT_MAJOR          = (__force vm_fault_t)0x0000004,
+	VM_FAULT_WRITE          = (__force vm_fault_t)0x0000008,
+	VM_FAULT_HWPOISON       = (__force vm_fault_t)0x0000010,
+	VM_FAULT_HWPOISON_LARGE = (__force vm_fault_t)0x0000020,
+	VM_FAULT_SIGSEGV        = (__force vm_fault_t)0x0000040,
+	VM_FAULT_NOPAGE         = (__force vm_fault_t)0x0000100,
+	VM_FAULT_LOCKED         = (__force vm_fault_t)0x0000200,
+	VM_FAULT_RETRY          = (__force vm_fault_t)0x0000400,
+	VM_FAULT_FALLBACK       = (__force vm_fault_t)0x0000800,
+	VM_FAULT_DONE_COW       = (__force vm_fault_t)0x0001000,
+	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x0002000,
+	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x0004000,
+	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x00f0000,
 };
 
 /* Encode hstate index for a hwpoisoned large page */
-- 
2.38.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 2/5] mm: Add VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

A handful of architectures (arm, s390, and soon RISC-V) define their
own internal fault codes, so instead dedicate a few standard codes as
being architecture-specific to avoid conflicts.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 include/linux/mm_types.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 758eb70829cb..df1aa8d58444 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -880,6 +880,11 @@ enum vm_fault_reason {
 	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x0002000,
 	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x0004000,
 	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x00f0000,
+	VM_FAULT_ARCH_0         = (__force vm_fault_t)0x0100000,
+	VM_FAULT_ARCH_1         = (__force vm_fault_t)0x0200000,
+	VM_FAULT_ARCH_2         = (__force vm_fault_t)0x0400000,
+	VM_FAULT_ARCH_3         = (__force vm_fault_t)0x0800000,
+	VM_FAULT_ARCH_4         = (__force vm_fault_t)0x1000000,
 };
 
 /* Encode hstate index for a hwpoisoned large page */
@@ -903,7 +908,12 @@ enum vm_fault_reason {
 	{ VM_FAULT_RETRY,               "RETRY" },	\
 	{ VM_FAULT_FALLBACK,            "FALLBACK" },	\
 	{ VM_FAULT_DONE_COW,            "DONE_COW" },	\
-	{ VM_FAULT_NEEDDSYNC,           "NEEDDSYNC" }
+	{ VM_FAULT_NEEDDSYNC,           "NEEDDSYNC" },  \
+	{ VM_FAULT_ARCH_0,              "ARCH_0" },     \
+	{ VM_FAULT_ARCH_1,              "ARCH_1" },     \
+	{ VM_FAULT_ARCH_2,              "ARCH_2" },     \
+	{ VM_FAULT_ARCH_3,              "ARCH_3" },     \
+	{ VM_FAULT_ARCH_4,              "ARCH_4" },     \
 
 struct vm_special_mapping {
 	const char *name;	/* The name, e.g. "[vdso]". */
-- 
2.38.1

[PATCH 2/5] mm: Add VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

A handful of architectures (arm, s390, and soon RISC-V) define their
own internal fault codes, so instead dedicate a few standard codes as
being architecture-specific to avoid conflicts.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 include/linux/mm_types.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 758eb70829cb..df1aa8d58444 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -880,6 +880,11 @@ enum vm_fault_reason {
 	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x0002000,
 	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x0004000,
 	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x00f0000,
+	VM_FAULT_ARCH_0         = (__force vm_fault_t)0x0100000,
+	VM_FAULT_ARCH_1         = (__force vm_fault_t)0x0200000,
+	VM_FAULT_ARCH_2         = (__force vm_fault_t)0x0400000,
+	VM_FAULT_ARCH_3         = (__force vm_fault_t)0x0800000,
+	VM_FAULT_ARCH_4         = (__force vm_fault_t)0x1000000,
 };
 
 /* Encode hstate index for a hwpoisoned large page */
@@ -903,7 +908,12 @@ enum vm_fault_reason {
 	{ VM_FAULT_RETRY,               "RETRY" },	\
 	{ VM_FAULT_FALLBACK,            "FALLBACK" },	\
 	{ VM_FAULT_DONE_COW,            "DONE_COW" },	\
-	{ VM_FAULT_NEEDDSYNC,           "NEEDDSYNC" }
+	{ VM_FAULT_NEEDDSYNC,           "NEEDDSYNC" },  \
+	{ VM_FAULT_ARCH_0,              "ARCH_0" },     \
+	{ VM_FAULT_ARCH_1,              "ARCH_1" },     \
+	{ VM_FAULT_ARCH_2,              "ARCH_2" },     \
+	{ VM_FAULT_ARCH_3,              "ARCH_3" },     \
+	{ VM_FAULT_ARCH_4,              "ARCH_4" },     \
 
 struct vm_special_mapping {
 	const char *name;	/* The name, e.g. "[vdso]". */
-- 
2.38.1


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

[PATCH 2/5] mm: Add VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

A handful of architectures (arm, s390, and soon RISC-V) define their
own internal fault codes, so instead dedicate a few standard codes as
being architecture-specific to avoid conflicts.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 include/linux/mm_types.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 758eb70829cb..df1aa8d58444 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -880,6 +880,11 @@ enum vm_fault_reason {
 	VM_FAULT_NEEDDSYNC      = (__force vm_fault_t)0x0002000,
 	VM_FAULT_COMPLETED      = (__force vm_fault_t)0x0004000,
 	VM_FAULT_HINDEX_MASK    = (__force vm_fault_t)0x00f0000,
+	VM_FAULT_ARCH_0         = (__force vm_fault_t)0x0100000,
+	VM_FAULT_ARCH_1         = (__force vm_fault_t)0x0200000,
+	VM_FAULT_ARCH_2         = (__force vm_fault_t)0x0400000,
+	VM_FAULT_ARCH_3         = (__force vm_fault_t)0x0800000,
+	VM_FAULT_ARCH_4         = (__force vm_fault_t)0x1000000,
 };
 
 /* Encode hstate index for a hwpoisoned large page */
@@ -903,7 +908,12 @@ enum vm_fault_reason {
 	{ VM_FAULT_RETRY,               "RETRY" },	\
 	{ VM_FAULT_FALLBACK,            "FALLBACK" },	\
 	{ VM_FAULT_DONE_COW,            "DONE_COW" },	\
-	{ VM_FAULT_NEEDDSYNC,           "NEEDDSYNC" }
+	{ VM_FAULT_NEEDDSYNC,           "NEEDDSYNC" },  \
+	{ VM_FAULT_ARCH_0,              "ARCH_0" },     \
+	{ VM_FAULT_ARCH_1,              "ARCH_1" },     \
+	{ VM_FAULT_ARCH_2,              "ARCH_2" },     \
+	{ VM_FAULT_ARCH_3,              "ARCH_3" },     \
+	{ VM_FAULT_ARCH_4,              "ARCH_4" },     \
 
 struct vm_special_mapping {
 	const char *name;	/* The name, e.g. "[vdso]". */
-- 
2.38.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 3/5] arm: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/arm/mm/fault.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 46cccd6bf705..7063b875b05f 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -201,8 +201,8 @@ void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 }
 
 #ifdef CONFIG_MMU
-#define VM_FAULT_BADMAP		((__force vm_fault_t)0x010000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t)0x020000)
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_0
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_1
 
 static inline bool is_permission_fault(unsigned int fsr)
 {
-- 
2.38.1

[PATCH 3/5] arm: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/arm/mm/fault.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 46cccd6bf705..7063b875b05f 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -201,8 +201,8 @@ void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 }
 
 #ifdef CONFIG_MMU
-#define VM_FAULT_BADMAP		((__force vm_fault_t)0x010000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t)0x020000)
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_0
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_1
 
 static inline bool is_permission_fault(unsigned int fsr)
 {
-- 
2.38.1


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

[PATCH 3/5] arm: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/arm/mm/fault.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 46cccd6bf705..7063b875b05f 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -201,8 +201,8 @@ void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 }
 
 #ifdef CONFIG_MMU
-#define VM_FAULT_BADMAP		((__force vm_fault_t)0x010000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t)0x020000)
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_0
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_1
 
 static inline bool is_permission_fault(unsigned int fsr)
 {
-- 
2.38.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 4/5] s390: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/s390/mm/fault.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 9649d9382e0a..464a74e52465 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -46,11 +46,11 @@
 #define __SUBCODE_MASK 0x0600
 #define __PF_RES_FIELD 0x8000000000000000ULL
 
-#define VM_FAULT_BADCONTEXT	((__force vm_fault_t) 0x010000)
-#define VM_FAULT_BADMAP		((__force vm_fault_t) 0x020000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t) 0x040000)
-#define VM_FAULT_SIGNAL		((__force vm_fault_t) 0x080000)
-#define VM_FAULT_PFAULT		((__force vm_fault_t) 0x100000)
+#define VM_FAULT_BADCONTEXT	VM_FAULT_ARCH_0
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_1
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_2
+#define VM_FAULT_SIGNAL		VM_FAULT_ARCH_3
+#define VM_FAULT_PFAULT		VM_FAULT_ARCH_4
 
 enum fault_type {
 	KERNEL_FAULT,
-- 
2.38.1

[PATCH 4/5] s390: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/s390/mm/fault.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 9649d9382e0a..464a74e52465 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -46,11 +46,11 @@
 #define __SUBCODE_MASK 0x0600
 #define __PF_RES_FIELD 0x8000000000000000ULL
 
-#define VM_FAULT_BADCONTEXT	((__force vm_fault_t) 0x010000)
-#define VM_FAULT_BADMAP		((__force vm_fault_t) 0x020000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t) 0x040000)
-#define VM_FAULT_SIGNAL		((__force vm_fault_t) 0x080000)
-#define VM_FAULT_PFAULT		((__force vm_fault_t) 0x100000)
+#define VM_FAULT_BADCONTEXT	VM_FAULT_ARCH_0
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_1
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_2
+#define VM_FAULT_SIGNAL		VM_FAULT_ARCH_3
+#define VM_FAULT_PFAULT		VM_FAULT_ARCH_4
 
 enum fault_type {
 	KERNEL_FAULT,
-- 
2.38.1


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

[PATCH 4/5] s390: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/s390/mm/fault.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 9649d9382e0a..464a74e52465 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -46,11 +46,11 @@
 #define __SUBCODE_MASK 0x0600
 #define __PF_RES_FIELD 0x8000000000000000ULL
 
-#define VM_FAULT_BADCONTEXT	((__force vm_fault_t) 0x010000)
-#define VM_FAULT_BADMAP		((__force vm_fault_t) 0x020000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t) 0x040000)
-#define VM_FAULT_SIGNAL		((__force vm_fault_t) 0x080000)
-#define VM_FAULT_PFAULT		((__force vm_fault_t) 0x100000)
+#define VM_FAULT_BADCONTEXT	VM_FAULT_ARCH_0
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_1
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_2
+#define VM_FAULT_SIGNAL		VM_FAULT_ARCH_3
+#define VM_FAULT_PFAULT		VM_FAULT_ARCH_4
 
 enum fault_type {
 	KERNEL_FAULT,
-- 
2.38.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 5/5] RISC-V: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/riscv/mm/fault.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 3fdc2eebdd36..bd990735aa90 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -202,8 +202,8 @@ static inline bool access_error(unsigned long cause, struct vm_area_struct *vma)
 	return false;
 }
 
-#define VM_FAULT_BADMAP		((__force vm_fault_t)0x010000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t)0x020000)
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_0
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_1
 
 static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr,
 				unsigned int mm_flags, struct pt_regs *regs)
-- 
2.38.1

[PATCH 5/5] RISC-V: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/riscv/mm/fault.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 3fdc2eebdd36..bd990735aa90 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -202,8 +202,8 @@ static inline bool access_error(unsigned long cause, struct vm_area_struct *vma)
 	return false;
 }
 
-#define VM_FAULT_BADMAP		((__force vm_fault_t)0x010000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t)0x020000)
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_0
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_1
 
 static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr,
 				unsigned int mm_flags, struct pt_regs *regs)
-- 
2.38.1


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

[PATCH 5/5] RISC-V: fault: Convert to VM_FAULT_ARCH_* codes

[Palmer Dabbelt]

These conflict with VM_FAULT_HINDEX_MASK, so move to some designated
arch-specific values.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
 arch/riscv/mm/fault.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 3fdc2eebdd36..bd990735aa90 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -202,8 +202,8 @@ static inline bool access_error(unsigned long cause, struct vm_area_struct *vma)
 	return false;
 }
 
-#define VM_FAULT_BADMAP		((__force vm_fault_t)0x010000)
-#define VM_FAULT_BADACCESS	((__force vm_fault_t)0x020000)
+#define VM_FAULT_BADMAP		VM_FAULT_ARCH_0
+#define VM_FAULT_BADACCESS	VM_FAULT_ARCH_1
 
 static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr,
 				unsigned int mm_flags, struct pt_regs *regs)
-- 
2.38.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 0/5] mm: Stop alaising VM_FAULT_HINDEX_MASK in arch code

[Palmer Dabbelt]

On Fri, 02 Dec 2022 19:03:51 PST (-0800), Palmer Dabbelt wrote:
> When reviewing
> <https://lore.kernel.org/r/20221029084715.3669204-1-tongtiangen@huawei.com>
> I noticed that the arch-specific VM_FAULT flags used by arm and s390
> alias with VM_FAULT_HINDEX_MASK.  I'm not sure if it's possible to
> manifest this as a bug, but it certainly seems fragile.
>
> The RISC-V patch is on top of the linked patch above, which isn't in any
> proper tree yet.  Everything else should apply to 6.1-rc1, but I'm in no
> particular rush to get that cleanup in so rush on my end for 6.2.  That
> said I figured it would be easier to send along this now, just in case
> someone who knows the MM code better thinks it can manifest as a bug.

Just pinging this one, I'm not sure if it was just bad timing on the 
last one.  That RISC-V patch is still sitting around outside my tree.

Re: [PATCH 0/5] mm: Stop alaising VM_FAULT_HINDEX_MASK in arch code

[Palmer Dabbelt]

On Fri, 02 Dec 2022 19:03:51 PST (-0800), Palmer Dabbelt wrote:
> When reviewing
> <https://lore.kernel.org/r/20221029084715.3669204-1-tongtiangen@huawei.com>
> I noticed that the arch-specific VM_FAULT flags used by arm and s390
> alias with VM_FAULT_HINDEX_MASK.  I'm not sure if it's possible to
> manifest this as a bug, but it certainly seems fragile.
>
> The RISC-V patch is on top of the linked patch above, which isn't in any
> proper tree yet.  Everything else should apply to 6.1-rc1, but I'm in no
> particular rush to get that cleanup in so rush on my end for 6.2.  That
> said I figured it would be easier to send along this now, just in case
> someone who knows the MM code better thinks it can manifest as a bug.

Just pinging this one, I'm not sure if it was just bad timing on the 
last one.  That RISC-V patch is still sitting around outside my tree.

_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

Re: [PATCH 0/5] mm: Stop alaising VM_FAULT_HINDEX_MASK in arch code

[Palmer Dabbelt]

On Fri, 02 Dec 2022 19:03:51 PST (-0800), Palmer Dabbelt wrote:
> When reviewing
> <https://lore.kernel.org/r/20221029084715.3669204-1-tongtiangen@huawei.com>
> I noticed that the arch-specific VM_FAULT flags used by arm and s390
> alias with VM_FAULT_HINDEX_MASK.  I'm not sure if it's possible to
> manifest this as a bug, but it certainly seems fragile.
>
> The RISC-V patch is on top of the linked patch above, which isn't in any
> proper tree yet.  Everything else should apply to 6.1-rc1, but I'm in no
> particular rush to get that cleanup in so rush on my end for 6.2.  That
> said I figured it would be easier to send along this now, just in case
> someone who knows the MM code better thinks it can manifest as a bug.

Just pinging this one, I'm not sure if it was just bad timing on the 
last one.  That RISC-V patch is still sitting around outside my tree.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel