* [PATCH 1/2] xen: make HYPERVISOR_get_debugreg() always_inline
2021-11-25 9:20 [PATCH 0/2] xen: make debugreg accessors always_inline Juergen Gross
@ 2021-11-25 9:20 ` Juergen Gross
2021-11-25 15:00 ` Andrew Cooper
2021-11-25 9:20 ` [PATCH 2/2] xen: make HYPERVISOR_set_debugreg() always_inline Juergen Gross
` (2 subsequent siblings)
3 siblings, 1 reply; 8+ messages in thread
From: Juergen Gross @ 2021-11-25 9:20 UTC (permalink / raw)
To: xen-devel, x86, linux-kernel
Cc: peterz, Juergen Gross, Boris Ostrovsky, Stefano Stabellini,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen,
H. Peter Anvin, kernel test robot
HYPERVISOR_get_debugreg() is being called from noinstr code, so it
should be attributed "always_inline".
Fixes: f4afb713e5c3a4419ba ("x86/xen: Make get_debugreg() noinstr")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
---
arch/x86/include/asm/xen/hypercall.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
index 0575f5863b7f..28ca1119606b 100644
--- a/arch/x86/include/asm/xen/hypercall.h
+++ b/arch/x86/include/asm/xen/hypercall.h
@@ -287,7 +287,7 @@ HYPERVISOR_set_debugreg(int reg, unsigned long value)
return _hypercall2(int, set_debugreg, reg, value);
}
-static inline unsigned long
+static __always_inline unsigned long
HYPERVISOR_get_debugreg(int reg)
{
return _hypercall1(unsigned long, get_debugreg, reg);
--
2.26.2
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH 1/2] xen: make HYPERVISOR_get_debugreg() always_inline
2021-11-25 9:20 ` [PATCH 1/2] xen: make HYPERVISOR_get_debugreg() always_inline Juergen Gross
@ 2021-11-25 15:00 ` Andrew Cooper
2021-11-25 15:04 ` Juergen Gross
0 siblings, 1 reply; 8+ messages in thread
From: Andrew Cooper @ 2021-11-25 15:00 UTC (permalink / raw)
To: Juergen Gross, xen-devel, x86, linux-kernel
Cc: peterz, Boris Ostrovsky, Stefano Stabellini, Thomas Gleixner,
Ingo Molnar, Borislav Petkov, Dave Hansen, H. Peter Anvin,
kernel test robot
On 25/11/2021 09:20, Juergen Gross wrote:
> HYPERVISOR_get_debugreg() is being called from noinstr code, so it
> should be attributed "always_inline".
>
> Fixes: f4afb713e5c3a4419ba ("x86/xen: Make get_debugreg() noinstr")
> Reported-by: kernel test robot <lkp@intel.com>
> Signed-off-by: Juergen Gross <jgross@suse.com>
> ---
> arch/x86/include/asm/xen/hypercall.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
> index 0575f5863b7f..28ca1119606b 100644
> --- a/arch/x86/include/asm/xen/hypercall.h
> +++ b/arch/x86/include/asm/xen/hypercall.h
> @@ -287,7 +287,7 @@ HYPERVISOR_set_debugreg(int reg, unsigned long value)
> return _hypercall2(int, set_debugreg, reg, value);
> }
>
> -static inline unsigned long
> +static __always_inline unsigned long
> HYPERVISOR_get_debugreg(int reg)
> {
> return _hypercall1(unsigned long, get_debugreg, reg);
All this is going to do is push the error one step further in.
Next, objtool will complain that hypercall_page isn't noinstr.
~Andrew
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH 1/2] xen: make HYPERVISOR_get_debugreg() always_inline
2021-11-25 15:00 ` Andrew Cooper
@ 2021-11-25 15:04 ` Juergen Gross
2021-11-25 15:41 ` Andrew Cooper
0 siblings, 1 reply; 8+ messages in thread
From: Juergen Gross @ 2021-11-25 15:04 UTC (permalink / raw)
To: Andrew Cooper, xen-devel, x86, linux-kernel
Cc: peterz, Boris Ostrovsky, Stefano Stabellini, Thomas Gleixner,
Ingo Molnar, Borislav Petkov, Dave Hansen, H. Peter Anvin,
kernel test robot
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On 25.11.21 16:00, Andrew Cooper wrote:
> On 25/11/2021 09:20, Juergen Gross wrote:
>> HYPERVISOR_get_debugreg() is being called from noinstr code, so it
>> should be attributed "always_inline".
>>
>> Fixes: f4afb713e5c3a4419ba ("x86/xen: Make get_debugreg() noinstr")
>> Reported-by: kernel test robot <lkp@intel.com>
>> Signed-off-by: Juergen Gross <jgross@suse.com>
>> ---
>> arch/x86/include/asm/xen/hypercall.h | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
>> index 0575f5863b7f..28ca1119606b 100644
>> --- a/arch/x86/include/asm/xen/hypercall.h
>> +++ b/arch/x86/include/asm/xen/hypercall.h
>> @@ -287,7 +287,7 @@ HYPERVISOR_set_debugreg(int reg, unsigned long value)
>> return _hypercall2(int, set_debugreg, reg, value);
>> }
>>
>> -static inline unsigned long
>> +static __always_inline unsigned long
>> HYPERVISOR_get_debugreg(int reg)
>> {
>> return _hypercall1(unsigned long, get_debugreg, reg);
>
> All this is going to do is push the error one step further in.
>
> Next, objtool will complain that hypercall_page isn't noinstr.
I don't think so:
.pushsection .noinstr.text, "ax"
.balign PAGE_SIZE
SYM_CODE_START(hypercall_page)
.rept (PAGE_SIZE / 32)
UNWIND_HINT_FUNC
.skip 31, 0x90
ret
.endr
Juergen
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^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH 1/2] xen: make HYPERVISOR_get_debugreg() always_inline
2021-11-25 15:04 ` Juergen Gross
@ 2021-11-25 15:41 ` Andrew Cooper
0 siblings, 0 replies; 8+ messages in thread
From: Andrew Cooper @ 2021-11-25 15:41 UTC (permalink / raw)
To: Juergen Gross, xen-devel, x86, linux-kernel
Cc: peterz, Boris Ostrovsky, Stefano Stabellini, Thomas Gleixner,
Ingo Molnar, Borislav Petkov, Dave Hansen, H. Peter Anvin,
kernel test robot
On 25/11/2021 15:04, Juergen Gross wrote:
> On 25.11.21 16:00, Andrew Cooper wrote:
>> On 25/11/2021 09:20, Juergen Gross wrote:
>>> HYPERVISOR_get_debugreg() is being called from noinstr code, so it
>>> should be attributed "always_inline".
>>>
>>> Fixes: f4afb713e5c3a4419ba ("x86/xen: Make get_debugreg() noinstr")
>>> Reported-by: kernel test robot <lkp@intel.com>
>>> Signed-off-by: Juergen Gross <jgross@suse.com>
>>> ---
>>> arch/x86/include/asm/xen/hypercall.h | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/arch/x86/include/asm/xen/hypercall.h
>>> b/arch/x86/include/asm/xen/hypercall.h
>>> index 0575f5863b7f..28ca1119606b 100644
>>> --- a/arch/x86/include/asm/xen/hypercall.h
>>> +++ b/arch/x86/include/asm/xen/hypercall.h
>>> @@ -287,7 +287,7 @@ HYPERVISOR_set_debugreg(int reg, unsigned long
>>> value)
>>> return _hypercall2(int, set_debugreg, reg, value);
>>> }
>>> -static inline unsigned long
>>> +static __always_inline unsigned long
>>> HYPERVISOR_get_debugreg(int reg)
>>> {
>>> return _hypercall1(unsigned long, get_debugreg, reg);
>>
>> All this is going to do is push the error one step further in.
>>
>> Next, objtool will complain that hypercall_page isn't noinstr.
>
> I don't think so:
>
> .pushsection .noinstr.text, "ax"
> .balign PAGE_SIZE
> SYM_CODE_START(hypercall_page)
> .rept (PAGE_SIZE / 32)
> UNWIND_HINT_FUNC
> .skip 31, 0x90
> ret
> .endr
/sigh yes. It would help if I was reading an up to date tree.
Sorry for the noise.
~Andrew
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 2/2] xen: make HYPERVISOR_set_debugreg() always_inline
2021-11-25 9:20 [PATCH 0/2] xen: make debugreg accessors always_inline Juergen Gross
2021-11-25 9:20 ` [PATCH 1/2] xen: make HYPERVISOR_get_debugreg() always_inline Juergen Gross
@ 2021-11-25 9:20 ` Juergen Gross
2021-11-25 15:39 ` [PATCH 0/2] xen: make debugreg accessors always_inline Boris Ostrovsky
2021-11-26 15:16 ` Boris Ostrovsky
3 siblings, 0 replies; 8+ messages in thread
From: Juergen Gross @ 2021-11-25 9:20 UTC (permalink / raw)
To: xen-devel, x86, linux-kernel
Cc: peterz, Juergen Gross, Boris Ostrovsky, Stefano Stabellini,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen,
H. Peter Anvin, kernel test robot
HYPERVISOR_set_debugreg() is being called from noinstr code, so it
should be attributed "always_inline".
Fixes: 7361fac0465ba96ec8f ("x86/xen: Make set_debugreg() noinstr")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
---
arch/x86/include/asm/xen/hypercall.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
index 28ca1119606b..e5e0fe10c692 100644
--- a/arch/x86/include/asm/xen/hypercall.h
+++ b/arch/x86/include/asm/xen/hypercall.h
@@ -281,7 +281,7 @@ HYPERVISOR_callback_op(int cmd, void *arg)
return _hypercall2(int, callback_op, cmd, arg);
}
-static inline int
+static __always_inline int
HYPERVISOR_set_debugreg(int reg, unsigned long value)
{
return _hypercall2(int, set_debugreg, reg, value);
--
2.26.2
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH 0/2] xen: make debugreg accessors always_inline
2021-11-25 9:20 [PATCH 0/2] xen: make debugreg accessors always_inline Juergen Gross
2021-11-25 9:20 ` [PATCH 1/2] xen: make HYPERVISOR_get_debugreg() always_inline Juergen Gross
2021-11-25 9:20 ` [PATCH 2/2] xen: make HYPERVISOR_set_debugreg() always_inline Juergen Gross
@ 2021-11-25 15:39 ` Boris Ostrovsky
2021-11-26 15:16 ` Boris Ostrovsky
3 siblings, 0 replies; 8+ messages in thread
From: Boris Ostrovsky @ 2021-11-25 15:39 UTC (permalink / raw)
To: Juergen Gross, xen-devel, x86, linux-kernel
Cc: peterz, Stefano Stabellini, Thomas Gleixner, Ingo Molnar,
Borislav Petkov, Dave Hansen, H. Peter Anvin
On 11/25/21 4:20 AM, Juergen Gross wrote:
> Juergen Gross (2):
> xen: make HYPERVISOR_get_debugreg() always_inline
> xen: make HYPERVISOR_set_debugreg() always_inline
>
> arch/x86/include/asm/xen/hypercall.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 0/2] xen: make debugreg accessors always_inline
2021-11-25 9:20 [PATCH 0/2] xen: make debugreg accessors always_inline Juergen Gross
` (2 preceding siblings ...)
2021-11-25 15:39 ` [PATCH 0/2] xen: make debugreg accessors always_inline Boris Ostrovsky
@ 2021-11-26 15:16 ` Boris Ostrovsky
3 siblings, 0 replies; 8+ messages in thread
From: Boris Ostrovsky @ 2021-11-26 15:16 UTC (permalink / raw)
To: Juergen Gross, xen-devel, x86, linux-kernel
Cc: peterz, Stefano Stabellini, Thomas Gleixner, Ingo Molnar,
Borislav Petkov, Dave Hansen, H. Peter Anvin
On 11/25/21 4:20 AM, Juergen Gross wrote:
> Juergen Gross (2):
> xen: make HYPERVISOR_get_debugreg() always_inline
> xen: make HYPERVISOR_set_debugreg() always_inline
>
> arch/x86/include/asm/xen/hypercall.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
Applied to for-linus-5.16c
-boris
^ permalink raw reply [flat|nested] 8+ messages in thread