[PATCH V3 0/4] riscv: mm: Fixup & Optimize COMPAT code

[PATCH V3 0/4] riscv: mm: Fixup & Optimize COMPAT code

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

When the task is in COMPAT mode, the TASK_SIZE should be 2GB, so
STACK_TOP_MAX and arch_get_mmap_end must be limited to 2 GB. This series
fixes the problem made by commit: add2cc6b6515 ("RISC-V: mm: Restrict
address space for sv39,sv48,sv57") and optimizes the related coding
convention of TASK_SIZE.

Changelog:
v3:
 - Remove wrong modification of arch_get_mmap_end
 - Remove is_compat_task optimization
 - Update comment log

v2:
https://lore.kernel.org/linux-riscv/20231221154702.2267684-1-guoren@kernel.org/
 - Separate rename from fixup
 - Add STACK_TOP_MAX fixup for compat
 - Add Cleanup & rename patches

v1:
https://lore.kernel.org/linux-riscv/20231219111701.1886903-1-guoren@kernel.org/

Guo Ren (4):
  riscv: mm: Fixup compat mode boot failure
  riscv: mm: Fixup compat arch_get_mmap_end
  riscv: mm: Remove unused TASK_SIZE_MIN
  riscv: mm: Optimize TASK_SIZE definition

 arch/riscv/include/asm/pgtable.h   | 7 +++----
 arch/riscv/include/asm/processor.h | 2 +-
 2 files changed, 4 insertions(+), 5 deletions(-)

-- 
2.40.1

[PATCH V3 0/4] riscv: mm: Fixup & Optimize COMPAT code

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

When the task is in COMPAT mode, the TASK_SIZE should be 2GB, so
STACK_TOP_MAX and arch_get_mmap_end must be limited to 2 GB. This series
fixes the problem made by commit: add2cc6b6515 ("RISC-V: mm: Restrict
address space for sv39,sv48,sv57") and optimizes the related coding
convention of TASK_SIZE.

Changelog:
v3:
 - Remove wrong modification of arch_get_mmap_end
 - Remove is_compat_task optimization
 - Update comment log

v2:
https://lore.kernel.org/linux-riscv/20231221154702.2267684-1-guoren@kernel.org/
 - Separate rename from fixup
 - Add STACK_TOP_MAX fixup for compat
 - Add Cleanup & rename patches

v1:
https://lore.kernel.org/linux-riscv/20231219111701.1886903-1-guoren@kernel.org/

Guo Ren (4):
  riscv: mm: Fixup compat mode boot failure
  riscv: mm: Fixup compat arch_get_mmap_end
  riscv: mm: Remove unused TASK_SIZE_MIN
  riscv: mm: Optimize TASK_SIZE definition

 arch/riscv/include/asm/pgtable.h   | 7 +++----
 arch/riscv/include/asm/processor.h | 2 +-
 2 files changed, 4 insertions(+), 5 deletions(-)

-- 
2.40.1


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[PATCH V3 1/4] riscv: mm: Fixup compat mode boot failure

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
will cause a user segment fault. Sometimes, it would cause boot
failure when the whole rootfs is rv32.

Freeing unused kernel image (initmem) memory: 2236K
Run /sbin/init as init process
Starting init: /sbin/init exists but couldn't execute it (error -14)
Run /etc/init as init process
...

Increase the TASK_SIZE to cover STACK_TOP.

Cc: stable@vger.kernel.org
Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
 arch/riscv/include/asm/pgtable.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index ab00235b018f..74ffb2178f54 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
 #define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
 
 #ifdef CONFIG_COMPAT
-#define TASK_SIZE_32	(_AC(0x80000000, UL) - PAGE_SIZE)
+#define TASK_SIZE_32	(_AC(0x80000000, UL))
 #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
 			 TASK_SIZE_32 : TASK_SIZE_64)
 #else
-- 
2.40.1

[PATCH V3 1/4] riscv: mm: Fixup compat mode boot failure

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
will cause a user segment fault. Sometimes, it would cause boot
failure when the whole rootfs is rv32.

Freeing unused kernel image (initmem) memory: 2236K
Run /sbin/init as init process
Starting init: /sbin/init exists but couldn't execute it (error -14)
Run /etc/init as init process
...

Increase the TASK_SIZE to cover STACK_TOP.

Cc: stable@vger.kernel.org
Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
 arch/riscv/include/asm/pgtable.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index ab00235b018f..74ffb2178f54 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
 #define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
 
 #ifdef CONFIG_COMPAT
-#define TASK_SIZE_32	(_AC(0x80000000, UL) - PAGE_SIZE)
+#define TASK_SIZE_32	(_AC(0x80000000, UL))
 #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
 			 TASK_SIZE_32 : TASK_SIZE_64)
 #else
-- 
2.40.1


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[PATCH V3 2/4] riscv: mm: Fixup compat arch_get_mmap_end

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

When the task is in COMPAT mode, the arch_get_mmap_end should be 2GB,
not TASK_SIZE_64. The TASK_SIZE has contained is_compat_mode()
detection, so change the definition of STACK_TOP_MAX to TASK_SIZE
directly.

Cc: stable@vger.kernel.org
Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
 arch/riscv/include/asm/processor.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
index f19f861cda54..e1944ff0757a 100644
--- a/arch/riscv/include/asm/processor.h
+++ b/arch/riscv/include/asm/processor.h
@@ -16,7 +16,7 @@
 
 #ifdef CONFIG_64BIT
 #define DEFAULT_MAP_WINDOW	(UL(1) << (MMAP_VA_BITS - 1))
-#define STACK_TOP_MAX		TASK_SIZE_64
+#define STACK_TOP_MAX		TASK_SIZE
 
 #define arch_get_mmap_end(addr, len, flags)			\
 ({								\
-- 
2.40.1

[PATCH V3 2/4] riscv: mm: Fixup compat arch_get_mmap_end

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

When the task is in COMPAT mode, the arch_get_mmap_end should be 2GB,
not TASK_SIZE_64. The TASK_SIZE has contained is_compat_mode()
detection, so change the definition of STACK_TOP_MAX to TASK_SIZE
directly.

Cc: stable@vger.kernel.org
Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
 arch/riscv/include/asm/processor.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
index f19f861cda54..e1944ff0757a 100644
--- a/arch/riscv/include/asm/processor.h
+++ b/arch/riscv/include/asm/processor.h
@@ -16,7 +16,7 @@
 
 #ifdef CONFIG_64BIT
 #define DEFAULT_MAP_WINDOW	(UL(1) << (MMAP_VA_BITS - 1))
-#define STACK_TOP_MAX		TASK_SIZE_64
+#define STACK_TOP_MAX		TASK_SIZE
 
 #define arch_get_mmap_end(addr, len, flags)			\
 ({								\
-- 
2.40.1


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[PATCH V3 3/4] riscv: mm: Remove unused TASK_SIZE_MIN

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

Remove TASK_SIZE_MIN because it's not used anymore.

Reviewed-by: Leonardo Bras <leobras@redhat.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
 arch/riscv/include/asm/pgtable.h | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 74ffb2178f54..e415582276ec 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -878,7 +878,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
  */
 #ifdef CONFIG_64BIT
 #define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
-#define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
 
 #ifdef CONFIG_COMPAT
 #define TASK_SIZE_32	(_AC(0x80000000, UL))
@@ -890,7 +889,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
 
 #else
 #define TASK_SIZE	FIXADDR_START
-#define TASK_SIZE_MIN	TASK_SIZE
 #endif
 
 #else /* CONFIG_MMU */
-- 
2.40.1

[PATCH V3 3/4] riscv: mm: Remove unused TASK_SIZE_MIN

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

Remove TASK_SIZE_MIN because it's not used anymore.

Reviewed-by: Leonardo Bras <leobras@redhat.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
 arch/riscv/include/asm/pgtable.h | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 74ffb2178f54..e415582276ec 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -878,7 +878,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
  */
 #ifdef CONFIG_64BIT
 #define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
-#define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
 
 #ifdef CONFIG_COMPAT
 #define TASK_SIZE_32	(_AC(0x80000000, UL))
@@ -890,7 +889,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
 
 #else
 #define TASK_SIZE	FIXADDR_START
-#define TASK_SIZE_MIN	TASK_SIZE
 #endif
 
 #else /* CONFIG_MMU */
-- 
2.40.1


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[PATCH V3 4/4] riscv: mm: Optimize TASK_SIZE definition

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

Unify the TASK_SIZE definition with VA_BITS for better readability.
Add COMPAT mode user address space info in the comment.

Reviewed-by: Leonardo Bras <leobras@redhat.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
 arch/riscv/include/asm/pgtable.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index e415582276ec..271565e1956f 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -866,6 +866,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
  * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
  * Task size is:
  * -        0x9fc00000	(~2.5GB) for RV32.
+ * -        0x80000000	(   2GB) for RV64 compat mode
  * -      0x4000000000	( 256GB) for RV64 using SV39 mmu
  * -    0x800000000000	( 128TB) for RV64 using SV48 mmu
  * - 0x100000000000000	(  64PB) for RV64 using SV57 mmu
@@ -877,10 +878,10 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
  * Similarly for SV57, bits 63–57 must be equal to bit 56.
  */
 #ifdef CONFIG_64BIT
-#define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
+#define TASK_SIZE_64	(UL(1) << (VA_BITS - 1))
 
 #ifdef CONFIG_COMPAT
-#define TASK_SIZE_32	(_AC(0x80000000, UL))
+#define TASK_SIZE_32	(UL(1) << (VA_BITS_SV32 - 1))
 #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
 			 TASK_SIZE_32 : TASK_SIZE_64)
 #else
-- 
2.40.1

[PATCH V3 4/4] riscv: mm: Optimize TASK_SIZE definition

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

Unify the TASK_SIZE definition with VA_BITS for better readability.
Add COMPAT mode user address space info in the comment.

Reviewed-by: Leonardo Bras <leobras@redhat.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
 arch/riscv/include/asm/pgtable.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index e415582276ec..271565e1956f 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -866,6 +866,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
  * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
  * Task size is:
  * -        0x9fc00000	(~2.5GB) for RV32.
+ * -        0x80000000	(   2GB) for RV64 compat mode
  * -      0x4000000000	( 256GB) for RV64 using SV39 mmu
  * -    0x800000000000	( 128TB) for RV64 using SV48 mmu
  * - 0x100000000000000	(  64PB) for RV64 using SV57 mmu
@@ -877,10 +878,10 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
  * Similarly for SV57, bits 63–57 must be equal to bit 56.
  */
 #ifdef CONFIG_64BIT
-#define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
+#define TASK_SIZE_64	(UL(1) << (VA_BITS - 1))
 
 #ifdef CONFIG_COMPAT
-#define TASK_SIZE_32	(_AC(0x80000000, UL))
+#define TASK_SIZE_32	(UL(1) << (VA_BITS_SV32 - 1))
 #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
 			 TASK_SIZE_32 : TASK_SIZE_64)
 #else
-- 
2.40.1


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Re: [PATCH V3 2/4] riscv: mm: Fixup compat arch_get_mmap_end

[Leonardo Bras]

On Fri, Dec 22, 2023 at 06:57:01AM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> When the task is in COMPAT mode, the arch_get_mmap_end should be 2GB,
> not TASK_SIZE_64. The TASK_SIZE has contained is_compat_mode()
> detection, so change the definition of STACK_TOP_MAX to TASK_SIZE
> directly.
> 
> Cc: stable@vger.kernel.org
> Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
>  arch/riscv/include/asm/processor.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
> index f19f861cda54..e1944ff0757a 100644
> --- a/arch/riscv/include/asm/processor.h
> +++ b/arch/riscv/include/asm/processor.h
> @@ -16,7 +16,7 @@
>  
>  #ifdef CONFIG_64BIT
>  #define DEFAULT_MAP_WINDOW	(UL(1) << (MMAP_VA_BITS - 1))
> -#define STACK_TOP_MAX		TASK_SIZE_64
> +#define STACK_TOP_MAX		TASK_SIZE
>  
>  #define arch_get_mmap_end(addr, len, flags)			\
>  ({								\
> -- 
> 2.40.1
> 


LGTM. 

FWIW:
Reviewed-by: Leonardo Bras <leobras@redhat.com>

Re: [PATCH V3 2/4] riscv: mm: Fixup compat arch_get_mmap_end

[Leonardo Bras]

On Fri, Dec 22, 2023 at 06:57:01AM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> When the task is in COMPAT mode, the arch_get_mmap_end should be 2GB,
> not TASK_SIZE_64. The TASK_SIZE has contained is_compat_mode()
> detection, so change the definition of STACK_TOP_MAX to TASK_SIZE
> directly.
> 
> Cc: stable@vger.kernel.org
> Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
>  arch/riscv/include/asm/processor.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
> index f19f861cda54..e1944ff0757a 100644
> --- a/arch/riscv/include/asm/processor.h
> +++ b/arch/riscv/include/asm/processor.h
> @@ -16,7 +16,7 @@
>  
>  #ifdef CONFIG_64BIT
>  #define DEFAULT_MAP_WINDOW	(UL(1) << (MMAP_VA_BITS - 1))
> -#define STACK_TOP_MAX		TASK_SIZE_64
> +#define STACK_TOP_MAX		TASK_SIZE
>  
>  #define arch_get_mmap_end(addr, len, flags)			\
>  ({								\
> -- 
> 2.40.1
> 


LGTM. 

FWIW:
Reviewed-by: Leonardo Bras <leobras@redhat.com>


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Re: [PATCH V3 1/4] riscv: mm: Fixup compat mode boot failure

[Leonardo Bras]

On Fri, Dec 22, 2023 at 06:57:00AM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
> the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
> will cause a user segment fault. Sometimes, it would cause boot
> failure when the whole rootfs is rv32.
> 
> Freeing unused kernel image (initmem) memory: 2236K
> Run /sbin/init as init process
> Starting init: /sbin/init exists but couldn't execute it (error -14)
> Run /etc/init as init process
> ...
> 
> Increase the TASK_SIZE to cover STACK_TOP.
> 
> Cc: stable@vger.kernel.org
> Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
>  arch/riscv/include/asm/pgtable.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index ab00235b018f..74ffb2178f54 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>  #define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
>  
>  #ifdef CONFIG_COMPAT
> -#define TASK_SIZE_32	(_AC(0x80000000, UL) - PAGE_SIZE)
> +#define TASK_SIZE_32	(_AC(0x80000000, UL))
>  #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
>  			 TASK_SIZE_32 : TASK_SIZE_64)
>  #else
> -- 
> 2.40.1
> 

I am not really involved in the issue this is solving, so I have no 
technical opinion on the solution. 

IIUC there should always be (TASK_SIZE >= STACK_TOP), so by itself this 
is fixing an issue.

I have reviewed the code and it does exactly as stated into the commit 
message, so FWIW:
Reviewed-by: Leonardo Bras <leobras@redhat.com>


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Re: [PATCH V3 1/4] riscv: mm: Fixup compat mode boot failure

[Leonardo Bras]

On Fri, Dec 22, 2023 at 06:57:00AM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
> the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
> will cause a user segment fault. Sometimes, it would cause boot
> failure when the whole rootfs is rv32.
> 
> Freeing unused kernel image (initmem) memory: 2236K
> Run /sbin/init as init process
> Starting init: /sbin/init exists but couldn't execute it (error -14)
> Run /etc/init as init process
> ...
> 
> Increase the TASK_SIZE to cover STACK_TOP.
> 
> Cc: stable@vger.kernel.org
> Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
>  arch/riscv/include/asm/pgtable.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index ab00235b018f..74ffb2178f54 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>  #define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
>  
>  #ifdef CONFIG_COMPAT
> -#define TASK_SIZE_32	(_AC(0x80000000, UL) - PAGE_SIZE)
> +#define TASK_SIZE_32	(_AC(0x80000000, UL))
>  #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
>  			 TASK_SIZE_32 : TASK_SIZE_64)
>  #else
> -- 
> 2.40.1
> 

I am not really involved in the issue this is solving, so I have no 
technical opinion on the solution. 

IIUC there should always be (TASK_SIZE >= STACK_TOP), so by itself this 
is fixing an issue.

I have reviewed the code and it does exactly as stated into the commit 
message, so FWIW:
Reviewed-by: Leonardo Bras <leobras@redhat.com>

Re: [PATCH V3 1/4] riscv: mm: Fixup compat mode boot failure

[Guo Ren]

On Sat, Dec 23, 2023 at 10:58 AM Leonardo Bras <leobras@redhat.com> wrote:
>
> On Fri, Dec 22, 2023 at 06:57:00AM -0500, guoren@kernel.org wrote:
> > From: Guo Ren <guoren@linux.alibaba.com>
> >
> > In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
> > the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
> > will cause a user segment fault. Sometimes, it would cause boot
> > failure when the whole rootfs is rv32.
> >
> > Freeing unused kernel image (initmem) memory: 2236K
> > Run /sbin/init as init process
> > Starting init: /sbin/init exists but couldn't execute it (error -14)
> > Run /etc/init as init process
> > ...
> >
> > Increase the TASK_SIZE to cover STACK_TOP.
> >
> > Cc: stable@vger.kernel.org
> > Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> > Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> > Signed-off-by: Guo Ren <guoren@kernel.org>
> > ---
> >  arch/riscv/include/asm/pgtable.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> > index ab00235b018f..74ffb2178f54 100644
> > --- a/arch/riscv/include/asm/pgtable.h
> > +++ b/arch/riscv/include/asm/pgtable.h
> > @@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
> >  #define TASK_SIZE_MIN        (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
> >
> >  #ifdef CONFIG_COMPAT
> > -#define TASK_SIZE_32 (_AC(0x80000000, UL) - PAGE_SIZE)
> > +#define TASK_SIZE_32 (_AC(0x80000000, UL))
> >  #define TASK_SIZE    (test_thread_flag(TIF_32BIT) ? \
> >                        TASK_SIZE_32 : TASK_SIZE_64)
> >  #else
> > --
> > 2.40.1
> >
>
> I am not really involved in the issue this is solving, so I have no
> technical opinion on the solution.
>
> IIUC there should always be (TASK_SIZE >= STACK_TOP), so by itself this
> is fixing an issue.
>
> I have reviewed the code and it does exactly as stated into the commit
> message, so FWIW:
> Reviewed-by: Leonardo Bras <leobras@redhat.com>
Thx,

I found this problem because it can't boot my rv32 buildroot-rootfs in
v6.6. But it's okay in v6.5. So I used git bisect and found commit:
add2cc6b6515 ("RISC-V: mm: Restrict address space for
sv39,sv48,sv57"), which caused that.

Ping Charlie, I hope it can be fixed in the v6.6 long-term version.

>



--
Best Regards
 Guo Ren

Re: [PATCH V3 1/4] riscv: mm: Fixup compat mode boot failure

[Guo Ren]

On Sat, Dec 23, 2023 at 10:58 AM Leonardo Bras <leobras@redhat.com> wrote:
>
> On Fri, Dec 22, 2023 at 06:57:00AM -0500, guoren@kernel.org wrote:
> > From: Guo Ren <guoren@linux.alibaba.com>
> >
> > In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
> > the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
> > will cause a user segment fault. Sometimes, it would cause boot
> > failure when the whole rootfs is rv32.
> >
> > Freeing unused kernel image (initmem) memory: 2236K
> > Run /sbin/init as init process
> > Starting init: /sbin/init exists but couldn't execute it (error -14)
> > Run /etc/init as init process
> > ...
> >
> > Increase the TASK_SIZE to cover STACK_TOP.
> >
> > Cc: stable@vger.kernel.org
> > Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> > Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> > Signed-off-by: Guo Ren <guoren@kernel.org>
> > ---
> >  arch/riscv/include/asm/pgtable.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> > index ab00235b018f..74ffb2178f54 100644
> > --- a/arch/riscv/include/asm/pgtable.h
> > +++ b/arch/riscv/include/asm/pgtable.h
> > @@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
> >  #define TASK_SIZE_MIN        (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
> >
> >  #ifdef CONFIG_COMPAT
> > -#define TASK_SIZE_32 (_AC(0x80000000, UL) - PAGE_SIZE)
> > +#define TASK_SIZE_32 (_AC(0x80000000, UL))
> >  #define TASK_SIZE    (test_thread_flag(TIF_32BIT) ? \
> >                        TASK_SIZE_32 : TASK_SIZE_64)
> >  #else
> > --
> > 2.40.1
> >
>
> I am not really involved in the issue this is solving, so I have no
> technical opinion on the solution.
>
> IIUC there should always be (TASK_SIZE >= STACK_TOP), so by itself this
> is fixing an issue.
>
> I have reviewed the code and it does exactly as stated into the commit
> message, so FWIW:
> Reviewed-by: Leonardo Bras <leobras@redhat.com>
Thx,

I found this problem because it can't boot my rv32 buildroot-rootfs in
v6.6. But it's okay in v6.5. So I used git bisect and found commit:
add2cc6b6515 ("RISC-V: mm: Restrict address space for
sv39,sv48,sv57"), which caused that.

Ping Charlie, I hope it can be fixed in the v6.6 long-term version.

>



--
Best Regards
 Guo Ren

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

Re: [PATCH V3 1/4] riscv: mm: Fixup compat mode boot failure

[Charlie Jenkins]

On Sat, Dec 23, 2023 at 11:07:29AM +0800, Guo Ren wrote:
> On Sat, Dec 23, 2023 at 10:58 AM Leonardo Bras <leobras@redhat.com> wrote:
> >
> > On Fri, Dec 22, 2023 at 06:57:00AM -0500, guoren@kernel.org wrote:
> > > From: Guo Ren <guoren@linux.alibaba.com>
> > >
> > > In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
> > > the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
> > > will cause a user segment fault. Sometimes, it would cause boot
> > > failure when the whole rootfs is rv32.
> > >
> > > Freeing unused kernel image (initmem) memory: 2236K
> > > Run /sbin/init as init process
> > > Starting init: /sbin/init exists but couldn't execute it (error -14)
> > > Run /etc/init as init process
> > > ...
> > >
> > > Increase the TASK_SIZE to cover STACK_TOP.
> > >
> > > Cc: stable@vger.kernel.org
> > > Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> > > Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> > > Signed-off-by: Guo Ren <guoren@kernel.org>
> > > ---
> > >  arch/riscv/include/asm/pgtable.h | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> > > index ab00235b018f..74ffb2178f54 100644
> > > --- a/arch/riscv/include/asm/pgtable.h
> > > +++ b/arch/riscv/include/asm/pgtable.h
> > > @@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
> > >  #define TASK_SIZE_MIN        (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
> > >
> > >  #ifdef CONFIG_COMPAT
> > > -#define TASK_SIZE_32 (_AC(0x80000000, UL) - PAGE_SIZE)
> > > +#define TASK_SIZE_32 (_AC(0x80000000, UL))
> > >  #define TASK_SIZE    (test_thread_flag(TIF_32BIT) ? \
> > >                        TASK_SIZE_32 : TASK_SIZE_64)
> > >  #else
> > > --
> > > 2.40.1
> > >
> >
> > I am not really involved in the issue this is solving, so I have no
> > technical opinion on the solution.
> >
> > IIUC there should always be (TASK_SIZE >= STACK_TOP), so by itself this
> > is fixing an issue.
> >
> > I have reviewed the code and it does exactly as stated into the commit
> > message, so FWIW:
> > Reviewed-by: Leonardo Bras <leobras@redhat.com>
> Thx,
> 
> I found this problem because it can't boot my rv32 buildroot-rootfs in
> v6.6. But it's okay in v6.5. So I used git bisect and found commit:
> add2cc6b6515 ("RISC-V: mm: Restrict address space for
> sv39,sv48,sv57"), which caused that.
> 
> Ping Charlie, I hope it can be fixed in the v6.6 long-term version.

I have looked at this more I do agree that this change makes sense. I
was thinking that it was valid to have STACK_TOP that was greater than
TASK_SIZE but I am no longer convinced that is true. Thank you for
looking into this.

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>

> 
> >
> 
> 
> 
> --
> Best Regards
>  Guo Ren

Re: [PATCH V3 1/4] riscv: mm: Fixup compat mode boot failure

[Charlie Jenkins]

On Sat, Dec 23, 2023 at 11:07:29AM +0800, Guo Ren wrote:
> On Sat, Dec 23, 2023 at 10:58 AM Leonardo Bras <leobras@redhat.com> wrote:
> >
> > On Fri, Dec 22, 2023 at 06:57:00AM -0500, guoren@kernel.org wrote:
> > > From: Guo Ren <guoren@linux.alibaba.com>
> > >
> > > In COMPAT mode, the STACK_TOP is DEFAULT_MAP_WINDOW (0x80000000), but
> > > the TASK_SIZE is 0x7fff000. When the user stack is upon 0x7fff000, it
> > > will cause a user segment fault. Sometimes, it would cause boot
> > > failure when the whole rootfs is rv32.
> > >
> > > Freeing unused kernel image (initmem) memory: 2236K
> > > Run /sbin/init as init process
> > > Starting init: /sbin/init exists but couldn't execute it (error -14)
> > > Run /etc/init as init process
> > > ...
> > >
> > > Increase the TASK_SIZE to cover STACK_TOP.
> > >
> > > Cc: stable@vger.kernel.org
> > > Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> > > Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> > > Signed-off-by: Guo Ren <guoren@kernel.org>
> > > ---
> > >  arch/riscv/include/asm/pgtable.h | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> > > index ab00235b018f..74ffb2178f54 100644
> > > --- a/arch/riscv/include/asm/pgtable.h
> > > +++ b/arch/riscv/include/asm/pgtable.h
> > > @@ -881,7 +881,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
> > >  #define TASK_SIZE_MIN        (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
> > >
> > >  #ifdef CONFIG_COMPAT
> > > -#define TASK_SIZE_32 (_AC(0x80000000, UL) - PAGE_SIZE)
> > > +#define TASK_SIZE_32 (_AC(0x80000000, UL))
> > >  #define TASK_SIZE    (test_thread_flag(TIF_32BIT) ? \
> > >                        TASK_SIZE_32 : TASK_SIZE_64)
> > >  #else
> > > --
> > > 2.40.1
> > >
> >
> > I am not really involved in the issue this is solving, so I have no
> > technical opinion on the solution.
> >
> > IIUC there should always be (TASK_SIZE >= STACK_TOP), so by itself this
> > is fixing an issue.
> >
> > I have reviewed the code and it does exactly as stated into the commit
> > message, so FWIW:
> > Reviewed-by: Leonardo Bras <leobras@redhat.com>
> Thx,
> 
> I found this problem because it can't boot my rv32 buildroot-rootfs in
> v6.6. But it's okay in v6.5. So I used git bisect and found commit:
> add2cc6b6515 ("RISC-V: mm: Restrict address space for
> sv39,sv48,sv57"), which caused that.
> 
> Ping Charlie, I hope it can be fixed in the v6.6 long-term version.

I have looked at this more I do agree that this change makes sense. I
was thinking that it was valid to have STACK_TOP that was greater than
TASK_SIZE but I am no longer convinced that is true. Thank you for
looking into this.

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>

> 
> >
> 
> 
> 
> --
> Best Regards
>  Guo Ren

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

Re: [PATCH V3 2/4] riscv: mm: Fixup compat arch_get_mmap_end

[Charlie Jenkins]

On Fri, Dec 22, 2023 at 11:51:48PM -0300, Leonardo Bras wrote:
> On Fri, Dec 22, 2023 at 06:57:01AM -0500, guoren@kernel.org wrote:
> > From: Guo Ren <guoren@linux.alibaba.com>
> > 
> > When the task is in COMPAT mode, the arch_get_mmap_end should be 2GB,
> > not TASK_SIZE_64. The TASK_SIZE has contained is_compat_mode()
> > detection, so change the definition of STACK_TOP_MAX to TASK_SIZE
> > directly.
> > 
> > Cc: stable@vger.kernel.org
> > Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> > Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> > Signed-off-by: Guo Ren <guoren@kernel.org>
> > ---
> >  arch/riscv/include/asm/processor.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
> > index f19f861cda54..e1944ff0757a 100644
> > --- a/arch/riscv/include/asm/processor.h
> > +++ b/arch/riscv/include/asm/processor.h
> > @@ -16,7 +16,7 @@
> >  
> >  #ifdef CONFIG_64BIT
> >  #define DEFAULT_MAP_WINDOW	(UL(1) << (MMAP_VA_BITS - 1))
> > -#define STACK_TOP_MAX		TASK_SIZE_64
> > +#define STACK_TOP_MAX		TASK_SIZE
> >  
> >  #define arch_get_mmap_end(addr, len, flags)			\
> >  ({								\
> > -- 
> > 2.40.1
> > 
> 
> 
> LGTM. 
> 
> FWIW:
> Reviewed-by: Leonardo Bras <leobras@redhat.com>

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>

> 

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

Re: [PATCH V3 2/4] riscv: mm: Fixup compat arch_get_mmap_end

[Charlie Jenkins]

On Fri, Dec 22, 2023 at 11:51:48PM -0300, Leonardo Bras wrote:
> On Fri, Dec 22, 2023 at 06:57:01AM -0500, guoren@kernel.org wrote:
> > From: Guo Ren <guoren@linux.alibaba.com>
> > 
> > When the task is in COMPAT mode, the arch_get_mmap_end should be 2GB,
> > not TASK_SIZE_64. The TASK_SIZE has contained is_compat_mode()
> > detection, so change the definition of STACK_TOP_MAX to TASK_SIZE
> > directly.
> > 
> > Cc: stable@vger.kernel.org
> > Fixes: add2cc6b6515 ("RISC-V: mm: Restrict address space for sv39,sv48,sv57")
> > Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> > Signed-off-by: Guo Ren <guoren@kernel.org>
> > ---
> >  arch/riscv/include/asm/processor.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
> > index f19f861cda54..e1944ff0757a 100644
> > --- a/arch/riscv/include/asm/processor.h
> > +++ b/arch/riscv/include/asm/processor.h
> > @@ -16,7 +16,7 @@
> >  
> >  #ifdef CONFIG_64BIT
> >  #define DEFAULT_MAP_WINDOW	(UL(1) << (MMAP_VA_BITS - 1))
> > -#define STACK_TOP_MAX		TASK_SIZE_64
> > +#define STACK_TOP_MAX		TASK_SIZE
> >  
> >  #define arch_get_mmap_end(addr, len, flags)			\
> >  ({								\
> > -- 
> > 2.40.1
> > 
> 
> 
> LGTM. 
> 
> FWIW:
> Reviewed-by: Leonardo Bras <leobras@redhat.com>

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>

> 

Re: [PATCH V3 0/4] riscv: mm: Fixup & Optimize COMPAT code

[patchwork-bot+linux-riscv]

Hello:

This series was applied to riscv/linux.git (for-next)
by Palmer Dabbelt <palmer@rivosinc.com>:

On Fri, 22 Dec 2023 06:56:59 -0500 you wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> When the task is in COMPAT mode, the TASK_SIZE should be 2GB, so
> STACK_TOP_MAX and arch_get_mmap_end must be limited to 2 GB. This series
> fixes the problem made by commit: add2cc6b6515 ("RISC-V: mm: Restrict
> address space for sv39,sv48,sv57") and optimizes the related coding
> convention of TASK_SIZE.
> 
> [...]

Here is the summary with links:
  - [V3,1/4] riscv: mm: Fixup compat mode boot failure
    https://git.kernel.org/riscv/c/5f449e245e5b
  - [V3,2/4] riscv: mm: Fixup compat arch_get_mmap_end
    https://git.kernel.org/riscv/c/97b7ac69be2e
  - [V3,3/4] riscv: mm: Remove unused TASK_SIZE_MIN
    (no matching commit)
  - [V3,4/4] riscv: mm: Optimize TASK_SIZE definition
    (no matching commit)

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH V3 0/4] riscv: mm: Fixup & Optimize COMPAT code

[patchwork-bot+linux-riscv]

Hello:

This series was applied to riscv/linux.git (for-next)
by Palmer Dabbelt <palmer@rivosinc.com>:

On Fri, 22 Dec 2023 06:56:59 -0500 you wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> When the task is in COMPAT mode, the TASK_SIZE should be 2GB, so
> STACK_TOP_MAX and arch_get_mmap_end must be limited to 2 GB. This series
> fixes the problem made by commit: add2cc6b6515 ("RISC-V: mm: Restrict
> address space for sv39,sv48,sv57") and optimizes the related coding
> convention of TASK_SIZE.
> 
> [...]

Here is the summary with links:
  - [V3,1/4] riscv: mm: Fixup compat mode boot failure
    https://git.kernel.org/riscv/c/5f449e245e5b
  - [V3,2/4] riscv: mm: Fixup compat arch_get_mmap_end
    https://git.kernel.org/riscv/c/97b7ac69be2e
  - [V3,3/4] riscv: mm: Remove unused TASK_SIZE_MIN
    (no matching commit)
  - [V3,4/4] riscv: mm: Optimize TASK_SIZE definition
    (no matching commit)

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html



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Re: [PATCH V3 3/4] riscv: mm: Remove unused TASK_SIZE_MIN

[Charlie Jenkins]

On Fri, Dec 22, 2023 at 06:57:02AM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> Remove TASK_SIZE_MIN because it's not used anymore.
> 
> Reviewed-by: Leonardo Bras <leobras@redhat.com>
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
>  arch/riscv/include/asm/pgtable.h | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index 74ffb2178f54..e415582276ec 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -878,7 +878,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>   */
>  #ifdef CONFIG_64BIT
>  #define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
> -#define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
>  
>  #ifdef CONFIG_COMPAT
>  #define TASK_SIZE_32	(_AC(0x80000000, UL))
> @@ -890,7 +889,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>  
>  #else
>  #define TASK_SIZE	FIXADDR_START
> -#define TASK_SIZE_MIN	TASK_SIZE
>  #endif
>  
>  #else /* CONFIG_MMU */
> -- 
> 2.40.1
> 

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>

Re: [PATCH V3 3/4] riscv: mm: Remove unused TASK_SIZE_MIN

[Charlie Jenkins]

On Fri, Dec 22, 2023 at 06:57:02AM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> Remove TASK_SIZE_MIN because it's not used anymore.
> 
> Reviewed-by: Leonardo Bras <leobras@redhat.com>
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
>  arch/riscv/include/asm/pgtable.h | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index 74ffb2178f54..e415582276ec 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -878,7 +878,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>   */
>  #ifdef CONFIG_64BIT
>  #define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
> -#define TASK_SIZE_MIN	(PGDIR_SIZE_L3 * PTRS_PER_PGD / 2)
>  
>  #ifdef CONFIG_COMPAT
>  #define TASK_SIZE_32	(_AC(0x80000000, UL))
> @@ -890,7 +889,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>  
>  #else
>  #define TASK_SIZE	FIXADDR_START
> -#define TASK_SIZE_MIN	TASK_SIZE
>  #endif
>  
>  #else /* CONFIG_MMU */
> -- 
> 2.40.1
> 

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>


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Re: [PATCH V3 4/4] riscv: mm: Optimize TASK_SIZE definition

[Charlie Jenkins]

On Fri, Dec 22, 2023 at 06:57:03AM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> Unify the TASK_SIZE definition with VA_BITS for better readability.
> Add COMPAT mode user address space info in the comment.
> 
> Reviewed-by: Leonardo Bras <leobras@redhat.com>
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
>  arch/riscv/include/asm/pgtable.h | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index e415582276ec..271565e1956f 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -866,6 +866,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>   * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
>   * Task size is:
>   * -        0x9fc00000	(~2.5GB) for RV32.
> + * -        0x80000000	(   2GB) for RV64 compat mode
>   * -      0x4000000000	( 256GB) for RV64 using SV39 mmu
>   * -    0x800000000000	( 128TB) for RV64 using SV48 mmu
>   * - 0x100000000000000	(  64PB) for RV64 using SV57 mmu
> @@ -877,10 +878,10 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>   * Similarly for SV57, bits 63–57 must be equal to bit 56.
>   */
>  #ifdef CONFIG_64BIT
> -#define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
> +#define TASK_SIZE_64	(UL(1) << (VA_BITS - 1))
>  
>  #ifdef CONFIG_COMPAT
> -#define TASK_SIZE_32	(_AC(0x80000000, UL))
> +#define TASK_SIZE_32	(UL(1) << (VA_BITS_SV32 - 1))
>  #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
>  			 TASK_SIZE_32 : TASK_SIZE_64)
>  #else
> -- 
> 2.40.1
> 

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>

Re: [PATCH V3 4/4] riscv: mm: Optimize TASK_SIZE definition

[Charlie Jenkins]

On Fri, Dec 22, 2023 at 06:57:03AM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> Unify the TASK_SIZE definition with VA_BITS for better readability.
> Add COMPAT mode user address space info in the comment.
> 
> Reviewed-by: Leonardo Bras <leobras@redhat.com>
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
>  arch/riscv/include/asm/pgtable.h | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index e415582276ec..271565e1956f 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -866,6 +866,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>   * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
>   * Task size is:
>   * -        0x9fc00000	(~2.5GB) for RV32.
> + * -        0x80000000	(   2GB) for RV64 compat mode
>   * -      0x4000000000	( 256GB) for RV64 using SV39 mmu
>   * -    0x800000000000	( 128TB) for RV64 using SV48 mmu
>   * - 0x100000000000000	(  64PB) for RV64 using SV57 mmu
> @@ -877,10 +878,10 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
>   * Similarly for SV57, bits 63–57 must be equal to bit 56.
>   */
>  #ifdef CONFIG_64BIT
> -#define TASK_SIZE_64	(PGDIR_SIZE * PTRS_PER_PGD / 2)
> +#define TASK_SIZE_64	(UL(1) << (VA_BITS - 1))
>  
>  #ifdef CONFIG_COMPAT
> -#define TASK_SIZE_32	(_AC(0x80000000, UL))
> +#define TASK_SIZE_32	(UL(1) << (VA_BITS_SV32 - 1))
>  #define TASK_SIZE	(test_thread_flag(TIF_32BIT) ? \
>  			 TASK_SIZE_32 : TASK_SIZE_64)
>  #else
> -- 
> 2.40.1
> 

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>


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