* [PATCH] powerpc/modules: If mprofile-kernel is enabled add it to vermagic
@ 2017-05-10 6:57 Michael Ellerman
2017-05-10 7:58 ` Balbir Singh
` (2 more replies)
0 siblings, 3 replies; 5+ messages in thread
From: Michael Ellerman @ 2017-05-10 6:57 UTC (permalink / raw)
To: linuxppc-dev; +Cc: jeyu, rusty, linux-kernel
On powerpc we can build the kernel with two different ABIs for mcount(), which
is used by ftrace. Kernels built with one ABI do not know how to load modules
built with the other ABI. The new style ABI is called "mprofile-kernel", for
want of a better name.
Currently if we build a module using the old style ABI, and the kernel with
mprofile-kernel, when we load the module we'll oops something like:
# insmod autofs4-no-mprofile-kernel.ko
ftrace-powerpc: Unexpected instruction f8810028 around bl _mcount
------------[ cut here ]------------
WARNING: CPU: 6 PID: 3759 at ../kernel/trace/ftrace.c:2024 ftrace_bug+0x2b8/0x3c0
CPU: 6 PID: 3759 Comm: insmod Not tainted 4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 #11
...
NIP [c0000000001eaa48] ftrace_bug+0x2b8/0x3c0
LR [c0000000001eaff8] ftrace_process_locs+0x4a8/0x590
Call Trace:
alloc_pages_current+0xc4/0x1d0 (unreliable)
ftrace_process_locs+0x4a8/0x590
load_module+0x1c8c/0x28f0
SyS_finit_module+0x110/0x140
system_call+0x38/0xfc
...
ftrace failed to modify
[<d000000002a31024>] 0xd000000002a31024
actual: 35:65:00:48
We can avoid this by including in the vermagic whether the kernel/module was
built with mprofile-kernel. Which results in:
# insmod autofs4-pg.ko
autofs4: version magic
'4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 SMP mod_unload modversions '
should be
'4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269-dirty SMP mod_unload modversions mprofile-kernel'
insmod: ERROR: could not insert module autofs4-pg.ko: Invalid module format
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/include/asm/module.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/powerpc/include/asm/module.h b/arch/powerpc/include/asm/module.h
index 53885512b8d3..6c0132c7212f 100644
--- a/arch/powerpc/include/asm/module.h
+++ b/arch/powerpc/include/asm/module.h
@@ -14,6 +14,10 @@
#include <asm-generic/module.h>
+#ifdef CC_USING_MPROFILE_KERNEL
+#define MODULE_ARCH_VERMAGIC "mprofile-kernel"
+#endif
+
#ifndef __powerpc64__
/*
* Thanks to Paul M for explaining this.
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] powerpc/modules: If mprofile-kernel is enabled add it to vermagic
2017-05-10 6:57 [PATCH] powerpc/modules: If mprofile-kernel is enabled add it to vermagic Michael Ellerman
@ 2017-05-10 7:58 ` Balbir Singh
2017-05-12 7:20 ` Jessica Yu
2017-05-17 9:34 ` Michael Ellerman
2 siblings, 0 replies; 5+ messages in thread
From: Balbir Singh @ 2017-05-10 7:58 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, Rusty Russell, Jessica Yu, linux-kernel
On Wed, May 10, 2017 at 4:57 PM, Michael Ellerman <mpe@ellerman.id.au> wrote:
> On powerpc we can build the kernel with two different ABIs for mcount(), which
> is used by ftrace. Kernels built with one ABI do not know how to load modules
> built with the other ABI. The new style ABI is called "mprofile-kernel", for
> want of a better name.
>
> Currently if we build a module using the old style ABI, and the kernel with
> mprofile-kernel, when we load the module we'll oops something like:
>
> # insmod autofs4-no-mprofile-kernel.ko
> ftrace-powerpc: Unexpected instruction f8810028 around bl _mcount
> ------------[ cut here ]------------
> WARNING: CPU: 6 PID: 3759 at ../kernel/trace/ftrace.c:2024 ftrace_bug+0x2b8/0x3c0
> CPU: 6 PID: 3759 Comm: insmod Not tainted 4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 #11
> ...
> NIP [c0000000001eaa48] ftrace_bug+0x2b8/0x3c0
> LR [c0000000001eaff8] ftrace_process_locs+0x4a8/0x590
> Call Trace:
> alloc_pages_current+0xc4/0x1d0 (unreliable)
> ftrace_process_locs+0x4a8/0x590
> load_module+0x1c8c/0x28f0
> SyS_finit_module+0x110/0x140
> system_call+0x38/0xfc
> ...
> ftrace failed to modify
> [<d000000002a31024>] 0xd000000002a31024
> actual: 35:65:00:48
>
> We can avoid this by including in the vermagic whether the kernel/module was
> built with mprofile-kernel. Which results in:
>
> # insmod autofs4-pg.ko
> autofs4: version magic
> '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 SMP mod_unload modversions '
> should be
> '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269-dirty SMP mod_unload modversions mprofile-kernel'
> insmod: ERROR: could not insert module autofs4-pg.ko: Invalid module format
>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> ---
> arch/powerpc/include/asm/module.h | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/module.h b/arch/powerpc/include/asm/module.h
> index 53885512b8d3..6c0132c7212f 100644
> --- a/arch/powerpc/include/asm/module.h
> +++ b/arch/powerpc/include/asm/module.h
> @@ -14,6 +14,10 @@
> #include <asm-generic/module.h>
>
>
> +#ifdef CC_USING_MPROFILE_KERNEL
> +#define MODULE_ARCH_VERMAGIC "mprofile-kernel"
> +#endif
> +
> #ifndef __powerpc64__
> /*
> * Thanks to Paul M for explaining this.
> --
Makes sense
Acked-by: Balbir Singh <bsingharora@gmail.com>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] powerpc/modules: If mprofile-kernel is enabled add it to vermagic
2017-05-10 6:57 [PATCH] powerpc/modules: If mprofile-kernel is enabled add it to vermagic Michael Ellerman
2017-05-10 7:58 ` Balbir Singh
@ 2017-05-12 7:20 ` Jessica Yu
2017-05-15 9:24 ` Michael Ellerman
2017-05-17 9:34 ` Michael Ellerman
2 siblings, 1 reply; 5+ messages in thread
From: Jessica Yu @ 2017-05-12 7:20 UTC (permalink / raw)
To: Michael Ellerman; +Cc: linuxppc-dev, rusty, linux-kernel
+++ Michael Ellerman [10/05/17 16:57 +1000]:
>On powerpc we can build the kernel with two different ABIs for mcount(), which
>is used by ftrace. Kernels built with one ABI do not know how to load modules
>built with the other ABI. The new style ABI is called "mprofile-kernel", for
>want of a better name.
>
>Currently if we build a module using the old style ABI, and the kernel with
>mprofile-kernel, when we load the module we'll oops something like:
>
> # insmod autofs4-no-mprofile-kernel.ko
> ftrace-powerpc: Unexpected instruction f8810028 around bl _mcount
> ------------[ cut here ]------------
> WARNING: CPU: 6 PID: 3759 at ../kernel/trace/ftrace.c:2024 ftrace_bug+0x2b8/0x3c0
> CPU: 6 PID: 3759 Comm: insmod Not tainted 4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 #11
> ...
> NIP [c0000000001eaa48] ftrace_bug+0x2b8/0x3c0
> LR [c0000000001eaff8] ftrace_process_locs+0x4a8/0x590
> Call Trace:
> alloc_pages_current+0xc4/0x1d0 (unreliable)
> ftrace_process_locs+0x4a8/0x590
> load_module+0x1c8c/0x28f0
> SyS_finit_module+0x110/0x140
> system_call+0x38/0xfc
> ...
> ftrace failed to modify
> [<d000000002a31024>] 0xd000000002a31024
> actual: 35:65:00:48
>
>We can avoid this by including in the vermagic whether the kernel/module was
>built with mprofile-kernel. Which results in:
>
> # insmod autofs4-pg.ko
> autofs4: version magic
> '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 SMP mod_unload modversions '
> should be
> '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269-dirty SMP mod_unload modversions mprofile-kernel'
> insmod: ERROR: could not insert module autofs4-pg.ko: Invalid module format
>
>Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Looks good to me:
Acked-by: Jessica Yu <jeyu@redhat.com>
>---
> arch/powerpc/include/asm/module.h | 4 ++++
> 1 file changed, 4 insertions(+)
>
>diff --git a/arch/powerpc/include/asm/module.h b/arch/powerpc/include/asm/module.h
>index 53885512b8d3..6c0132c7212f 100644
>--- a/arch/powerpc/include/asm/module.h
>+++ b/arch/powerpc/include/asm/module.h
>@@ -14,6 +14,10 @@
> #include <asm-generic/module.h>
>
>
>+#ifdef CC_USING_MPROFILE_KERNEL
>+#define MODULE_ARCH_VERMAGIC "mprofile-kernel"
>+#endif
>+
> #ifndef __powerpc64__
> /*
> * Thanks to Paul M for explaining this.
>--
>2.7.4
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] powerpc/modules: If mprofile-kernel is enabled add it to vermagic
2017-05-12 7:20 ` Jessica Yu
@ 2017-05-15 9:24 ` Michael Ellerman
0 siblings, 0 replies; 5+ messages in thread
From: Michael Ellerman @ 2017-05-15 9:24 UTC (permalink / raw)
To: Jessica Yu; +Cc: linuxppc-dev, rusty, linux-kernel
Jessica Yu <jeyu@redhat.com> writes:
> +++ Michael Ellerman [10/05/17 16:57 +1000]:
>>On powerpc we can build the kernel with two different ABIs for mcount(), which
>>is used by ftrace. Kernels built with one ABI do not know how to load modules
>>built with the other ABI. The new style ABI is called "mprofile-kernel", for
>>want of a better name.
>>
>>Currently if we build a module using the old style ABI, and the kernel with
>>mprofile-kernel, when we load the module we'll oops something like:
>>
>> # insmod autofs4-no-mprofile-kernel.ko
>> ftrace-powerpc: Unexpected instruction f8810028 around bl _mcount
>> ------------[ cut here ]------------
>> WARNING: CPU: 6 PID: 3759 at ../kernel/trace/ftrace.c:2024 ftrace_bug+0x2b8/0x3c0
>> CPU: 6 PID: 3759 Comm: insmod Not tainted 4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 #11
>> ...
>> NIP [c0000000001eaa48] ftrace_bug+0x2b8/0x3c0
>> LR [c0000000001eaff8] ftrace_process_locs+0x4a8/0x590
>> Call Trace:
>> alloc_pages_current+0xc4/0x1d0 (unreliable)
>> ftrace_process_locs+0x4a8/0x590
>> load_module+0x1c8c/0x28f0
>> SyS_finit_module+0x110/0x140
>> system_call+0x38/0xfc
>> ...
>> ftrace failed to modify
>> [<d000000002a31024>] 0xd000000002a31024
>> actual: 35:65:00:48
>>
>>We can avoid this by including in the vermagic whether the kernel/module was
>>built with mprofile-kernel. Which results in:
>>
>> # insmod autofs4-pg.ko
>> autofs4: version magic
>> '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 SMP mod_unload modversions '
>> should be
>> '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269-dirty SMP mod_unload modversions mprofile-kernel'
>> insmod: ERROR: could not insert module autofs4-pg.ko: Invalid module format
>>
>>Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
>
> Looks good to me:
>
> Acked-by: Jessica Yu <jeyu@redhat.com>
Thanks.
cheers
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: powerpc/modules: If mprofile-kernel is enabled add it to vermagic
2017-05-10 6:57 [PATCH] powerpc/modules: If mprofile-kernel is enabled add it to vermagic Michael Ellerman
2017-05-10 7:58 ` Balbir Singh
2017-05-12 7:20 ` Jessica Yu
@ 2017-05-17 9:34 ` Michael Ellerman
2 siblings, 0 replies; 5+ messages in thread
From: Michael Ellerman @ 2017-05-17 9:34 UTC (permalink / raw)
To: Michael Ellerman, linuxppc-dev; +Cc: rusty, jeyu, linux-kernel
On Wed, 2017-05-10 at 06:57:49 UTC, Michael Ellerman wrote:
> On powerpc we can build the kernel with two different ABIs for mcount(), which
> is used by ftrace. Kernels built with one ABI do not know how to load modules
> built with the other ABI. The new style ABI is called "mprofile-kernel", for
> want of a better name.
>
> Currently if we build a module using the old style ABI, and the kernel with
> mprofile-kernel, when we load the module we'll oops something like:
>
> # insmod autofs4-no-mprofile-kernel.ko
> ftrace-powerpc: Unexpected instruction f8810028 around bl _mcount
> ------------[ cut here ]------------
> WARNING: CPU: 6 PID: 3759 at ../kernel/trace/ftrace.c:2024 ftrace_bug+0x2b8/0x3c0
> CPU: 6 PID: 3759 Comm: insmod Not tainted 4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 #11
> ...
> NIP [c0000000001eaa48] ftrace_bug+0x2b8/0x3c0
> LR [c0000000001eaff8] ftrace_process_locs+0x4a8/0x590
> Call Trace:
> alloc_pages_current+0xc4/0x1d0 (unreliable)
> ftrace_process_locs+0x4a8/0x590
> load_module+0x1c8c/0x28f0
> SyS_finit_module+0x110/0x140
> system_call+0x38/0xfc
> ...
> ftrace failed to modify
> [<d000000002a31024>] 0xd000000002a31024
> actual: 35:65:00:48
>
> We can avoid this by including in the vermagic whether the kernel/module was
> built with mprofile-kernel. Which results in:
>
> # insmod autofs4-pg.ko
> autofs4: version magic
> '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269 SMP mod_unload modversions '
> should be
> '4.11.0-rc3-gcc-5.4.1-00017-g5a61ef74f269-dirty SMP mod_unload modversions mprofile-kernel'
> insmod: ERROR: could not insert module autofs4-pg.ko: Invalid module format
>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> Acked-by: Balbir Singh <bsingharora@gmail.com>
> Acked-by: Jessica Yu <jeyu@redhat.com>
Applied to powerpc fixes.
https://git.kernel.org/powerpc/c/43e24e82f35291d4c1ca78877ce1b2
cheers
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2017-05-17 9:34 UTC | newest]
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2017-05-10 6:57 [PATCH] powerpc/modules: If mprofile-kernel is enabled add it to vermagic Michael Ellerman
2017-05-10 7:58 ` Balbir Singh
2017-05-12 7:20 ` Jessica Yu
2017-05-15 9:24 ` Michael Ellerman
2017-05-17 9:34 ` Michael Ellerman
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