The implict soft-mask table addresses get relocated if they use a
relative symbol like a label. This is right for code that runs relocated
but not for unrelocated. The scv interrupt vectors run unrelocated, so
absolute addresses are required for their soft-mask table entry.
This fixes crashing with relocated kernels, usually an asynchronous
interrupt hitting in the scv handler, then hitting the trap that checks
whether r1 is in userspace.
Cc: Hari Bathini <hbath...@linux.ibm.com>
Fixes: 325678fd0522 ("powerpc/64s: add a table of implicit soft-masked
addresses")
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
arch/powerpc/kernel/exceptions-64s.S | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/exceptions-64s.S
b/arch/powerpc/kernel/exceptions-64s.S
index 4aec59a77d4c..37859e62a8dc 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -812,7 +812,6 @@ __start_interrupts:
* syscall register convention is in Documentation/powerpc/syscall64-abi.rst
*/
EXC_VIRT_BEGIN(system_call_vectored, 0x3000, 0x1000)
-1:
/* SCV 0 */
mr r9,r13
GET_PACA(r13)
@@ -842,10 +841,12 @@ EXC_VIRT_BEGIN(system_call_vectored, 0x3000, 0x1000)
b system_call_vectored_sigill
#endif
.endr
-2:
EXC_VIRT_END(system_call_vectored, 0x3000, 0x1000)
-SOFT_MASK_TABLE(1b, 2b) // Treat scv vectors as soft-masked, see comment above.
+// Treat scv vectors as soft-masked, see comment above.
+// Use absolute values rather than labels here, so they don't get relocated,
+// because this code runs unrelocated.
+SOFT_MASK_TABLE(0xc000000000003000, 0xc000000000004000)
#ifdef CONFIG_RELOCATABLE
TRAMP_VIRT_BEGIN(system_call_vectored_tramp)
--
2.23.0
