[v2,1/3] hw/cxl/cxl-host: Fix segmentation fault when getting cxl-fmw property

Commit Message

Jonathan Cameron July 5, 2024, 11:39 a.m. UTC

From: Zhao Liu <[e-mail]>

QEMU crashes (Segmentation fault) when getting cxl-fmw property via
qmp:

(QEMU) qom-get path=machine property=cxl-fmw

This issue is caused by accessing wrong callback (opaque) type in
machine_get_cfmw().

cxl_machine_init() sets the callback as `CXLState *` type but
machine_get_cfmw() treats the callback as
`CXLFixedMemoryWindowOptionsList **`.

Fix this error by casting opaque to `CXLState *` type in
machine_get_cfmw().

Fixes: 03b39fcf64bc ("hw/cxl: Make the CXL fixed memory window setup a machine parameter.")
Signed-off-by: Zhao Liu <[e-mail]>
Reviewed-by: Li Zhijian <[e-mail]>
Reviewed-by: Xingtao Yao <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jonathan Cameron <[e-mail]>
---
 hw/cxl/cxl-host.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Michael Tokarev July 24, 2024, 4:53 a.m. UTC | #1

05.07.2024 14:39, Jonathan Cameron via wrote:
> From: Zhao Liu <[e-mail]>
> 
> QEMU crashes (Segmentation fault) when getting cxl-fmw property via
> qmp:
> 
> (QEMU) qom-get path=machine property=cxl-fmw
> 
> This issue is caused by accessing wrong callback (opaque) type in
> machine_get_cfmw().
> 
> cxl_machine_init() sets the callback as `CXLState *` type but
> machine_get_cfmw() treats the callback as
> `CXLFixedMemoryWindowOptionsList **`.
> 
> Fix this error by casting opaque to `CXLState *` type in
> machine_get_cfmw().
> 
> Fixes: 03b39fcf64bc ("hw/cxl: Make the CXL fixed memory window setup a machine parameter.")
> Signed-off-by: Zhao Liu <[e-mail]>
> Reviewed-by: Li Zhijian <[e-mail]>
> Reviewed-by: Xingtao Yao <[e-mail]>
> Link: https://lore.kernel.org/r/[e-mail]
> Signed-off-by: Jonathan Cameron <[e-mail]>

Is this a stable@ material?

Thanks,

/mjt

Jonathan Cameron July 25, 2024, 4:54 p.m. UTC | #2

On Wed, 24 Jul 2024 07:53:48 +0300
Michael Tokarev <[e-mail]> wrote:

> 05.07.2024 14:39, Jonathan Cameron via wrote:
> > From: Zhao Liu <[e-mail]>
> > 
> > QEMU crashes (Segmentation fault) when getting cxl-fmw property via
> > qmp:
> > 
> > (QEMU) qom-get path=machine property=cxl-fmw
> > 
> > This issue is caused by accessing wrong callback (opaque) type in
> > machine_get_cfmw().
> > 
> > cxl_machine_init() sets the callback as `CXLState *` type but
> > machine_get_cfmw() treats the callback as
> > `CXLFixedMemoryWindowOptionsList **`.
> > 
> > Fix this error by casting opaque to `CXLState *` type in
> > machine_get_cfmw().
> > 
> > Fixes: 03b39fcf64bc ("hw/cxl: Make the CXL fixed memory window setup a machine parameter.")
> > Signed-off-by: Zhao Liu <[e-mail]>
> > Reviewed-by: Li Zhijian <[e-mail]>
> > Reviewed-by: Xingtao Yao <[e-mail]>
> > Link: https://lore.kernel.org/r/[e-mail]
> > Signed-off-by: Jonathan Cameron <[e-mail]>  
> 
> Is this a stable@ material?

Yes please

Thanks,

Jonathan

> 
> Thanks,
> 
> /mjt
>

Patch

diff --git a/hw/cxl/cxl-host.c b/hw/cxl/cxl-host.c
index c5f5fcfd64..e9f2543c43 100644
--- a/hw/cxl/cxl-host.c
+++ b/hw/cxl/cxl-host.c
@@ -315,7 +315,8 @@  static void machine_set_cxl(Object *obj, Visitor *v, const char *name,
 static void machine_get_cfmw(Object *obj, Visitor *v, const char *name,
                              void *opaque, Error **errp)
 {
-    CXLFixedMemoryWindowOptionsList **list = opaque;
+    CXLState *state = opaque;
+    CXLFixedMemoryWindowOptionsList **list = &state->cfmw_list;
 
     visit_type_CXLFixedMemoryWindowOptionsList(v, name, list, errp);
 }