[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH v4 01/10] xen/arm64: Added handling of the trapped access to OSLSR register



Hi,

On 15/05/18 12:44, Mirela Simonovic wrote:
Linux/dom0 accesses OSLSR register when saving CPU context during the
suspend procedure. Xen traps access to this register, but has no handling
for it. Consequently, Xen injects undef exception to linux, causing it to
crash. This patch adds handling of the trapped access to OSLSR as ro/raz.

Signed-off-by: Mirela Simonovic <mirela.simonovic@xxxxxxxxxx>
Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Acked-by: Julien Grall <julien.grall@xxxxxxx>

---
CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
CC: Julien Grall <julien.grall@xxxxxxx>
---
Changes in v2:
- Commit message fix (arm64 related change instead of arm)
- Add Stefano's reviewed-by

Changes in v3:
- Added Julien's acked-by
---
  xen/arch/arm/arm64/vsysreg.c | 3 ++-
  1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xen/arch/arm/arm64/vsysreg.c b/xen/arch/arm/arm64/vsysreg.c
index c57ac12503..8f80e1735e 100644
--- a/xen/arch/arm/arm64/vsysreg.c
+++ b/xen/arch/arm/arm64/vsysreg.c
@@ -57,13 +57,14 @@ void do_sysreg(struct cpu_user_regs *regs,
       * ARMv8 (DDI 0487A.d): D1-1509 Table D1-58
       *
       * Unhandled:
-     *    OSLSR_EL1
       *    DBGPRCR_EL1
       */
      case HSR_SYSREG_OSLAR_EL1:
          return handle_wo_wi(regs, regidx, hsr.sysreg.read, hsr, 1);
      case HSR_SYSREG_OSDLR_EL1:
          return handle_raz_wi(regs, regidx, hsr.sysreg.read, hsr, 1);
+    case HSR_SYSREG_OSLSR_EL1:
+        return handle_ro_raz(regs, regidx, hsr.sysreg.read, hsr, 1);

Looking at this patch again, OSLM (bit[3] and bit[1]) should be 10 as all other values are reserved. So you want to set bit 3 when the guest read it.

Cheers,

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.