[PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma

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* [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma
@ 2022-03-31  5:59 Alistair Francis
  2022-03-31  6:38 ` Anup Patel
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: Alistair Francis @ 2022-03-31  5:59 UTC (permalink / raw)
  To: aou, linux-riscv, palmer, paul.walmsley
  Cc: atishp, anup, guoren, alistair23, linux-kernel, Alistair Francis

From: Alistair Francis <alistair.francis@wdc.com>

When we set the value of context.id using __new_context() we set both
the asid and the current_version with this return statement in
__new_context():

    return asid | ver;

This means that when local_flush_tlb_all_asid() is called with the asid
specified from context.id we can write the incorrect value.

We get away with this as hardware ignores the extra bits, as the RISC-V
specification states:

"bits SXLEN-1:ASIDMAX of the value held in rs2 are reserved for future
standard use. Until their use is defined by a standard extension, they
should be zeroed by software and ignored by current implementations."

but it is still a bug and worth addressing as we are incorrectly setting
extra bits.

This patch uses asid_mask when calling sfence.vma to ensure the asid is
always the correct len (ASIDLEN). This is similar to what we do in
arch/riscv/mm/context.c.

Fixes: 3f1e782998cd ("riscv: add ASID-based tlbflushing methods")
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
---
v3:
 - Use helper function
v2:
 - Pass in pre-masked value

 arch/riscv/include/asm/mmu_context.h | 2 ++
 arch/riscv/mm/context.c              | 5 +++++
 arch/riscv/mm/tlbflush.c             | 2 +-
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h
index 7030837adc1a..94e82c9e17eb 100644
--- a/arch/riscv/include/asm/mmu_context.h
+++ b/arch/riscv/include/asm/mmu_context.h
@@ -16,6 +16,8 @@
 void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 	struct task_struct *task);
 
+unsigned long get_mm_asid(struct mm_struct *mm);
+
 #define activate_mm activate_mm
 static inline void activate_mm(struct mm_struct *prev,
 			       struct mm_struct *next)
diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
index 7acbfbd14557..14aec5bacbc1 100644
--- a/arch/riscv/mm/context.c
+++ b/arch/riscv/mm/context.c
@@ -302,6 +302,11 @@ static inline void flush_icache_deferred(struct mm_struct *mm, unsigned int cpu)
 #endif
 }
 
+unsigned long get_mm_asid(struct mm_struct *mm)
+{
+	return atomic_long_read(&mm->context.id) & asid_mask;
+}
+
 void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 	struct task_struct *task)
 {
diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
index 37ed760d007c..9c89c4951bee 100644
--- a/arch/riscv/mm/tlbflush.c
+++ b/arch/riscv/mm/tlbflush.c
@@ -42,7 +42,7 @@ static void __sbi_tlb_flush_range(struct mm_struct *mm, unsigned long start,
 	/* check if the tlbflush needs to be sent to other CPUs */
 	broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
 	if (static_branch_unlikely(&use_asid_allocator)) {
-		unsigned long asid = atomic_long_read(&mm->context.id);
+		unsigned long asid = get_mm_asid(mm);
 
 		if (broadcast) {
 			sbi_remote_sfence_vma_asid(cmask, start, size, asid);
-- 
2.35.1


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http://lists.infradead.org/mailman/listinfo/linux-riscv

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma
  2022-03-31  5:59 [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma Alistair Francis
@ 2022-03-31  6:38 ` Anup Patel
  2022-03-31  7:25 ` Guo Ren
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Anup Patel @ 2022-03-31  6:38 UTC (permalink / raw)
  To: Alistair Francis
  Cc: Albert Ou, linux-riscv, Palmer Dabbelt, Paul Walmsley,
	Atish Patra, Guo Ren, Alistair Francis,
	linux-kernel@vger.kernel.org List, Alistair Francis

On Thu, Mar 31, 2022 at 11:29 AM Alistair Francis
<alistair.francis@opensource.wdc.com> wrote:
>
> From: Alistair Francis <alistair.francis@wdc.com>
>
> When we set the value of context.id using __new_context() we set both
> the asid and the current_version with this return statement in
> __new_context():
>
>     return asid | ver;
>
> This means that when local_flush_tlb_all_asid() is called with the asid
> specified from context.id we can write the incorrect value.
>
> We get away with this as hardware ignores the extra bits, as the RISC-V
> specification states:
>
> "bits SXLEN-1:ASIDMAX of the value held in rs2 are reserved for future
> standard use. Until their use is defined by a standard extension, they
> should be zeroed by software and ignored by current implementations."
>
> but it is still a bug and worth addressing as we are incorrectly setting
> extra bits.
>
> This patch uses asid_mask when calling sfence.vma to ensure the asid is
> always the correct len (ASIDLEN). This is similar to what we do in
> arch/riscv/mm/context.c.
>
> Fixes: 3f1e782998cd ("riscv: add ASID-based tlbflushing methods")
> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

Looks good to me.

Reviewed-by: Anup Patel <anup@brainfault.org>

Regards,
Anup

> ---
> v3:
>  - Use helper function
> v2:
>  - Pass in pre-masked value
>
>  arch/riscv/include/asm/mmu_context.h | 2 ++
>  arch/riscv/mm/context.c              | 5 +++++
>  arch/riscv/mm/tlbflush.c             | 2 +-
>  3 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h
> index 7030837adc1a..94e82c9e17eb 100644
> --- a/arch/riscv/include/asm/mmu_context.h
> +++ b/arch/riscv/include/asm/mmu_context.h
> @@ -16,6 +16,8 @@
>  void switch_mm(struct mm_struct *prev, struct mm_struct *next,
>         struct task_struct *task);
>
> +unsigned long get_mm_asid(struct mm_struct *mm);
> +
>  #define activate_mm activate_mm
>  static inline void activate_mm(struct mm_struct *prev,
>                                struct mm_struct *next)
> diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
> index 7acbfbd14557..14aec5bacbc1 100644
> --- a/arch/riscv/mm/context.c
> +++ b/arch/riscv/mm/context.c
> @@ -302,6 +302,11 @@ static inline void flush_icache_deferred(struct mm_struct *mm, unsigned int cpu)
>  #endif
>  }
>
> +unsigned long get_mm_asid(struct mm_struct *mm)
> +{
> +       return atomic_long_read(&mm->context.id) & asid_mask;
> +}
> +
>  void switch_mm(struct mm_struct *prev, struct mm_struct *next,
>         struct task_struct *task)
>  {
> diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
> index 37ed760d007c..9c89c4951bee 100644
> --- a/arch/riscv/mm/tlbflush.c
> +++ b/arch/riscv/mm/tlbflush.c
> @@ -42,7 +42,7 @@ static void __sbi_tlb_flush_range(struct mm_struct *mm, unsigned long start,
>         /* check if the tlbflush needs to be sent to other CPUs */
>         broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
>         if (static_branch_unlikely(&use_asid_allocator)) {
> -               unsigned long asid = atomic_long_read(&mm->context.id);
> +               unsigned long asid = get_mm_asid(mm);
>
>                 if (broadcast) {
>                         sbi_remote_sfence_vma_asid(cmask, start, size, asid);
> --
> 2.35.1
>

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

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma
  2022-03-31  5:59 [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma Alistair Francis
  2022-03-31  6:38 ` Anup Patel
@ 2022-03-31  7:25 ` Guo Ren
  2022-03-31  9:45 ` kernel test robot
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Guo Ren @ 2022-03-31  7:25 UTC (permalink / raw)
  To: Alistair Francis
  Cc: Albert Ou, linux-riscv, Palmer Dabbelt, Paul Walmsley, atishp,
	Anup Patel, Alistair Francis, Linux Kernel Mailing List,
	Alistair Francis

Reviewed-by: Guo Ren <guoren@kernel.org>

On Thu, Mar 31, 2022 at 1:59 PM Alistair Francis
<alistair.francis@opensource.wdc.com> wrote:
>
> From: Alistair Francis <alistair.francis@wdc.com>
>
> When we set the value of context.id using __new_context() we set both
> the asid and the current_version with this return statement in
> __new_context():
>
>     return asid | ver;
>
> This means that when local_flush_tlb_all_asid() is called with the asid
> specified from context.id we can write the incorrect value.
>
> We get away with this as hardware ignores the extra bits, as the RISC-V
> specification states:
>
> "bits SXLEN-1:ASIDMAX of the value held in rs2 are reserved for future
> standard use. Until their use is defined by a standard extension, they
> should be zeroed by software and ignored by current implementations."
>
> but it is still a bug and worth addressing as we are incorrectly setting
> extra bits.
>
> This patch uses asid_mask when calling sfence.vma to ensure the asid is
> always the correct len (ASIDLEN). This is similar to what we do in
> arch/riscv/mm/context.c.
>
> Fixes: 3f1e782998cd ("riscv: add ASID-based tlbflushing methods")
> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
> ---
> v3:
>  - Use helper function
> v2:
>  - Pass in pre-masked value
>
>  arch/riscv/include/asm/mmu_context.h | 2 ++
>  arch/riscv/mm/context.c              | 5 +++++
>  arch/riscv/mm/tlbflush.c             | 2 +-
>  3 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h
> index 7030837adc1a..94e82c9e17eb 100644
> --- a/arch/riscv/include/asm/mmu_context.h
> +++ b/arch/riscv/include/asm/mmu_context.h
> @@ -16,6 +16,8 @@
>  void switch_mm(struct mm_struct *prev, struct mm_struct *next,
>         struct task_struct *task);
>
> +unsigned long get_mm_asid(struct mm_struct *mm);
> +
>  #define activate_mm activate_mm
>  static inline void activate_mm(struct mm_struct *prev,
>                                struct mm_struct *next)
> diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
> index 7acbfbd14557..14aec5bacbc1 100644
> --- a/arch/riscv/mm/context.c
> +++ b/arch/riscv/mm/context.c
> @@ -302,6 +302,11 @@ static inline void flush_icache_deferred(struct mm_struct *mm, unsigned int cpu)
>  #endif
>  }
>
> +unsigned long get_mm_asid(struct mm_struct *mm)
> +{
> +       return atomic_long_read(&mm->context.id) & asid_mask;
> +}
> +
>  void switch_mm(struct mm_struct *prev, struct mm_struct *next,
>         struct task_struct *task)
>  {
> diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
> index 37ed760d007c..9c89c4951bee 100644
> --- a/arch/riscv/mm/tlbflush.c
> +++ b/arch/riscv/mm/tlbflush.c
> @@ -42,7 +42,7 @@ static void __sbi_tlb_flush_range(struct mm_struct *mm, unsigned long start,
>         /* check if the tlbflush needs to be sent to other CPUs */
>         broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
>         if (static_branch_unlikely(&use_asid_allocator)) {
> -               unsigned long asid = atomic_long_read(&mm->context.id);
> +               unsigned long asid = get_mm_asid(mm);
>
>                 if (broadcast) {
>                         sbi_remote_sfence_vma_asid(cmask, start, size, asid);
> --
> 2.35.1
>


-- 
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/

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

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma
  2022-03-31  5:59 [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma Alistair Francis
  2022-03-31  6:38 ` Anup Patel
  2022-03-31  7:25 ` Guo Ren
@ 2022-03-31  9:45 ` kernel test robot
  2022-03-31 13:51 ` kernel test robot
  2022-04-01  0:06 ` Palmer Dabbelt
  4 siblings, 0 replies; 6+ messages in thread
From: kernel test robot @ 2022-03-31  9:45 UTC (permalink / raw)
  To: Alistair Francis, aou, linux-riscv, palmer, paul.walmsley
  Cc: kbuild-all, atishp, anup, guoren, alistair23, linux-kernel,
	Alistair Francis

Hi Alistair,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v5.17 next-20220331]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Alistair-Francis/riscv-Ensure-only-ASIDLEN-is-used-for-sfence-vma/20220331-140116
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 787af64d05cd528aac9ad16752d11bb1c6061bb9
config: riscv-nommu_k210_defconfig (https://download.01.org/0day-ci/archive/20220331/202203311731.xi8xw0gy-lkp@intel.com/config)
compiler: riscv64-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/162147030f410152d028af446a7383e3c9410f55
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Alistair-Francis/riscv-Ensure-only-ASIDLEN-is-used-for-sfence-vma/20220331-140116
        git checkout 162147030f410152d028af446a7383e3c9410f55
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=riscv SHELL=/bin/bash arch/riscv/mm/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   arch/riscv/mm/context.c: In function 'get_mm_asid':
>> arch/riscv/mm/context.c:307:45: error: 'mm_context_t' has no member named 'id'
     307 |         return atomic_long_read(&mm->context.id) & asid_mask;
         |                                             ^
>> arch/riscv/mm/context.c:307:52: error: 'asid_mask' undeclared (first use in this function); did you mean 'pid_task'?
     307 |         return atomic_long_read(&mm->context.id) & asid_mask;
         |                                                    ^~~~~~~~~
         |                                                    pid_task
   arch/riscv/mm/context.c:307:52: note: each undeclared identifier is reported only once for each function it appears in
   arch/riscv/mm/context.c:308:1: error: control reaches end of non-void function [-Werror=return-type]
     308 | }
         | ^
   cc1: some warnings being treated as errors


vim +307 arch/riscv/mm/context.c

   304	
   305	unsigned long get_mm_asid(struct mm_struct *mm)
   306	{
 > 307		return atomic_long_read(&mm->context.id) & asid_mask;
   308	}
   309	

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

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

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma
  2022-03-31  5:59 [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma Alistair Francis
                   ` (2 preceding siblings ...)
  2022-03-31  9:45 ` kernel test robot
@ 2022-03-31 13:51 ` kernel test robot
  2022-04-01  0:06 ` Palmer Dabbelt
  4 siblings, 0 replies; 6+ messages in thread
From: kernel test robot @ 2022-03-31 13:51 UTC (permalink / raw)
  To: Alistair Francis, aou, linux-riscv, palmer, paul.walmsley
  Cc: llvm, kbuild-all, atishp, anup, guoren, alistair23, linux-kernel,
	Alistair Francis

Hi Alistair,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v5.17 next-20220331]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Alistair-Francis/riscv-Ensure-only-ASIDLEN-is-used-for-sfence-vma/20220331-140116
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 787af64d05cd528aac9ad16752d11bb1c6061bb9
config: riscv-randconfig-c006-20220331 (https://download.01.org/0day-ci/archive/20220331/202203312110.VamttjhO-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 881350a92d821d4f8e4fa648443ed1d17e251188)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install riscv cross compiling tool for clang build
        # apt-get install binutils-riscv64-linux-gnu
        # https://github.com/intel-lab-lkp/linux/commit/162147030f410152d028af446a7383e3c9410f55
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Alistair-Francis/riscv-Ensure-only-ASIDLEN-is-used-for-sfence-vma/20220331-140116
        git checkout 162147030f410152d028af446a7383e3c9410f55
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash arch/riscv/mm/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> arch/riscv/mm/context.c:307:39: error: no member named 'id' in 'mm_context_t'
           return atomic_long_read(&mm->context.id) & asid_mask;
                                    ~~~~~~~~~~~ ^
>> arch/riscv/mm/context.c:307:45: error: use of undeclared identifier 'asid_mask'
           return atomic_long_read(&mm->context.id) & asid_mask;
                                                      ^
   2 errors generated.


vim +307 arch/riscv/mm/context.c

   304	
   305	unsigned long get_mm_asid(struct mm_struct *mm)
   306	{
 > 307		return atomic_long_read(&mm->context.id) & asid_mask;
   308	}
   309	

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

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

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma
  2022-03-31  5:59 [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma Alistair Francis
                   ` (3 preceding siblings ...)
  2022-03-31 13:51 ` kernel test robot
@ 2022-04-01  0:06 ` Palmer Dabbelt
  4 siblings, 0 replies; 6+ messages in thread
From: Palmer Dabbelt @ 2022-04-01  0:06 UTC (permalink / raw)
  To: alistair.francis
  Cc: aou, linux-riscv, Paul Walmsley, Atish Patra, anup, guoren,
	alistair23, linux-kernel, Alistair Francis

On Wed, 30 Mar 2022 22:59:06 PDT (-0700), alistair.francis@opensource.wdc.com wrote:
> From: Alistair Francis <alistair.francis@wdc.com>
>
> When we set the value of context.id using __new_context() we set both
> the asid and the current_version with this return statement in
> __new_context():
>
>     return asid | ver;
>
> This means that when local_flush_tlb_all_asid() is called with the asid
> specified from context.id we can write the incorrect value.
>
> We get away with this as hardware ignores the extra bits, as the RISC-V
> specification states:
>
> "bits SXLEN-1:ASIDMAX of the value held in rs2 are reserved for future
> standard use. Until their use is defined by a standard extension, they
> should be zeroed by software and ignored by current implementations."
>
> but it is still a bug and worth addressing as we are incorrectly setting
> extra bits.
>
> This patch uses asid_mask when calling sfence.vma to ensure the asid is
> always the correct len (ASIDLEN). This is similar to what we do in
> arch/riscv/mm/context.c.
>
> Fixes: 3f1e782998cd ("riscv: add ASID-based tlbflushing methods")
> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
> ---
> v3:
>  - Use helper function
> v2:
>  - Pass in pre-masked value
>
>  arch/riscv/include/asm/mmu_context.h | 2 ++
>  arch/riscv/mm/context.c              | 5 +++++
>  arch/riscv/mm/tlbflush.c             | 2 +-
>  3 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h
> index 7030837adc1a..94e82c9e17eb 100644
> --- a/arch/riscv/include/asm/mmu_context.h
> +++ b/arch/riscv/include/asm/mmu_context.h
> @@ -16,6 +16,8 @@
>  void switch_mm(struct mm_struct *prev, struct mm_struct *next,
>  	struct task_struct *task);
>  
> +unsigned long get_mm_asid(struct mm_struct *mm);
> +
>  #define activate_mm activate_mm
>  static inline void activate_mm(struct mm_struct *prev,
>  			       struct mm_struct *next)
> diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
> index 7acbfbd14557..14aec5bacbc1 100644
> --- a/arch/riscv/mm/context.c
> +++ b/arch/riscv/mm/context.c
> @@ -302,6 +302,11 @@ static inline void flush_icache_deferred(struct mm_struct *mm, unsigned int cpu)
>  #endif
>  }
>  
> +unsigned long get_mm_asid(struct mm_struct *mm)
> +{
> +	return atomic_long_read(&mm->context.id) & asid_mask;
> +}
> +
>  void switch_mm(struct mm_struct *prev, struct mm_struct *next,
>  	struct task_struct *task)
>  {
> diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
> index 37ed760d007c..9c89c4951bee 100644
> --- a/arch/riscv/mm/tlbflush.c
> +++ b/arch/riscv/mm/tlbflush.c
> @@ -42,7 +42,7 @@ static void __sbi_tlb_flush_range(struct mm_struct *mm, unsigned long start,
>  	/* check if the tlbflush needs to be sent to other CPUs */
>  	broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
>  	if (static_branch_unlikely(&use_asid_allocator)) {
> -		unsigned long asid = atomic_long_read(&mm->context.id);
> +		unsigned long asid = get_mm_asid(mm);
>  
>  		if (broadcast) {
>  			sbi_remote_sfence_vma_asid(cmask, start, size, asid);
> -- 
> 2.35.1

The autobuilders are finding some failures.  I think this

    diff --git a/arch/riscv/mm/context.c b/arch/riscv/mm/context.c
    index 6df4f22f0a3c..8a9c7bc2297a 100644
    --- a/arch/riscv/mm/context.c
    +++ b/arch/riscv/mm/context.c
    @@ -12,6 +12,7 @@
     #include <linux/slab.h>
     #include <linux/spinlock.h>
     #include <linux/static_key.h>
    +#include <asm/atomic.h>
     #include <asm/tlbflush.h>
     #include <asm/cacheflush.h>
     #include <asm/mmu_context.h>

should do it, I've squashed that in and put it on palmer/riscv-asidlen 
so the autobuilders can find it.  It's going to be too late for rc1, but 
this seems fine for fixes so it's no big deal.

Feel free to send a v4 if there's anything else, but if that's enough to 
fix it then no need to.  If there's no v4 and nothing goes wrong, I'll 
cherry-pick it past rc1 when I re-fork my fixes tree.

Thanks!

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^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2022-04-01  0:06 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2022-03-31  5:59 [PATCH v3] riscv: Ensure only ASIDLEN is used for sfence.vma Alistair Francis
2022-03-31  6:38 ` Anup Patel
2022-03-31  7:25 ` Guo Ren
2022-03-31  9:45 ` kernel test robot
2022-03-31 13:51 ` kernel test robot
2022-04-01  0:06 ` Palmer Dabbelt

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