Re: [PATCH v2] x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled
On 27/01/2021 13:59, Jürgen Groß wrote:
> On 27.01.21 12:23, Andrew Cooper wrote:
>> On 27/01/2021 10:26, Jürgen Groß wrote:
>>> On 27.01.21 10:43, Andrew Cooper wrote:
On 27/01/2021 09:38, Juergen Gross wrote:
> diff --git a/arch/x86/xen/enlighten_pv.c
> b/arch/x86/xen/enlighten_pv.c
> index 4409306364dc..ca5ac10fcbf7 100644
> --- a/arch/x86/xen/enlighten_pv.c
> +++ b/arch/x86/xen/enlighten_pv.c
> @@ -583,6 +583,12 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_debug)
> exc_debug(regs);
> }
> +DEFINE_IDTENTRY_RAW(exc_xen_unknown_trap)
> +{
> + /* This should never happen and there is no way to handle it. */
> + panic("Unknown trap in Xen PV mode.");
Looks much better. How about including regs->entry_vector here,
just to
short circuit the inevitable swearing which will accompany
encountering
this panic() ?
>>>
>>> You are aware the regs parameter is struct pt_regs *, not the Xen
>>> struct cpu_user_regs *?
>>
>> Yes, but I was assuming that they both contained the same information.
>>
>>>
>>> So I have no idea how I should get this information without creating
>>> a per-vector handler.
>>
>> Oh - that's dull.
>>
>> Fine then. Reviewed-by: Andrew Cooper
>>
>
> I think I'll switch the panic() to printk(); BUG(); in order to have
> more diagnostic data. Can I keep your R-b: with that modification?
Yeah. Sounds good.
~Andrew
Re: [PATCH v2] x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled
On 27.01.21 12:23, Andrew Cooper wrote:
On 27/01/2021 10:26, Jürgen Groß wrote:
On 27.01.21 10:43, Andrew Cooper wrote:
On 27/01/2021 09:38, Juergen Gross wrote:
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 4409306364dc..ca5ac10fcbf7 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -583,6 +583,12 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_debug)
exc_debug(regs);
}
+DEFINE_IDTENTRY_RAW(exc_xen_unknown_trap)
+{
+ /* This should never happen and there is no way to handle it. */
+ panic("Unknown trap in Xen PV mode.");
Looks much better. How about including regs->entry_vector here, just to
short circuit the inevitable swearing which will accompany encountering
this panic() ?
You are aware the regs parameter is struct pt_regs *, not the Xen
struct cpu_user_regs *?
Yes, but I was assuming that they both contained the same information.
So I have no idea how I should get this information without creating
a per-vector handler.
Oh - that's dull.
Fine then. Reviewed-by: Andrew Cooper
I think I'll switch the panic() to printk(); BUG(); in order to have
more diagnostic data. Can I keep your R-b: with that modification?
Juergen
OpenPGP_0xB0DE9DD628BF132F.asc
Description: application/pgp-keys
OpenPGP_signature
Description: OpenPGP digital signature
Re: [PATCH v2] x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled
On 27/01/2021 10:26, Jürgen Groß wrote:
> On 27.01.21 10:43, Andrew Cooper wrote:
>> On 27/01/2021 09:38, Juergen Gross wrote:
>>> diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
>>> index 4409306364dc..ca5ac10fcbf7 100644
>>> --- a/arch/x86/xen/enlighten_pv.c
>>> +++ b/arch/x86/xen/enlighten_pv.c
>>> @@ -583,6 +583,12 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_debug)
>>> exc_debug(regs);
>>> }
>>> +DEFINE_IDTENTRY_RAW(exc_xen_unknown_trap)
>>> +{
>>> + /* This should never happen and there is no way to handle it. */
>>> + panic("Unknown trap in Xen PV mode.");
>>
>> Looks much better. How about including regs->entry_vector here, just to
>> short circuit the inevitable swearing which will accompany encountering
>> this panic() ?
>
> You are aware the regs parameter is struct pt_regs *, not the Xen
> struct cpu_user_regs *?
Yes, but I was assuming that they both contained the same information.
>
> So I have no idea how I should get this information without creating
> a per-vector handler.
Oh - that's dull.
Fine then. Reviewed-by: Andrew Cooper
Re: [PATCH v2] x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled
On 27.01.2021 11:26, Jürgen Groß wrote:
> On 27.01.21 10:43, Andrew Cooper wrote:
>> On 27/01/2021 09:38, Juergen Gross wrote:
>>> diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
>>> index 4409306364dc..ca5ac10fcbf7 100644
>>> --- a/arch/x86/xen/enlighten_pv.c
>>> +++ b/arch/x86/xen/enlighten_pv.c
>>> @@ -583,6 +583,12 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_debug)
>>> exc_debug(regs);
>>> }
>>>
>>> +DEFINE_IDTENTRY_RAW(exc_xen_unknown_trap)
>>> +{
>>> + /* This should never happen and there is no way to handle it. */
>>> + panic("Unknown trap in Xen PV mode.");
>>
>> Looks much better. How about including regs->entry_vector here, just to
>> short circuit the inevitable swearing which will accompany encountering
>> this panic() ?
>
> You are aware the regs parameter is struct pt_regs *, not the Xen
> struct cpu_user_regs *?
>
> So I have no idea how I should get this information without creating
> a per-vector handler.
Maybe log _RET_IP_ then (ideally decoded to a symbol), to give at
least some hint as to where this was coming from?
Jan
Re: [PATCH v2] x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled
On 27.01.21 10:43, Andrew Cooper wrote:
On 27/01/2021 09:38, Juergen Gross wrote:
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 4409306364dc..ca5ac10fcbf7 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -583,6 +583,12 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_debug)
exc_debug(regs);
}
+DEFINE_IDTENTRY_RAW(exc_xen_unknown_trap)
+{
+ /* This should never happen and there is no way to handle it. */
+ panic("Unknown trap in Xen PV mode.");
Looks much better. How about including regs->entry_vector here, just to
short circuit the inevitable swearing which will accompany encountering
this panic() ?
You are aware the regs parameter is struct pt_regs *, not the Xen
struct cpu_user_regs *?
So I have no idea how I should get this information without creating
a per-vector handler.
Juergen
OpenPGP_0xB0DE9DD628BF132F.asc
Description: application/pgp-keys
OpenPGP_signature
Description: OpenPGP digital signature
Re: [PATCH v2] x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled
On 27/01/2021 09:38, Juergen Gross wrote:
> diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
> index 4409306364dc..ca5ac10fcbf7 100644
> --- a/arch/x86/xen/enlighten_pv.c
> +++ b/arch/x86/xen/enlighten_pv.c
> @@ -583,6 +583,12 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_debug)
> exc_debug(regs);
> }
>
> +DEFINE_IDTENTRY_RAW(exc_xen_unknown_trap)
> +{
> + /* This should never happen and there is no way to handle it. */
> + panic("Unknown trap in Xen PV mode.");
Looks much better. How about including regs->entry_vector here, just to
short circuit the inevitable swearing which will accompany encountering
this panic() ?
~Andrew
