[Qemu-devel] [PATCH 1/9] linux-user: fix segmentation fault passing with h2g(x) != x

[Alexander Graf <agraf@suse.de>]

When forwarding a segmentation fault into the guest process, we were passing
the host's address directly into the guest process's signal descriptor.

That obviously confused the guest process, since it didn't know what to make
of the (usually 32-bit truncated) address. Passing in h2g(address) makes the
guest process a lot happier.

This fixes java running in arm-linux-user for me.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 user-exec.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/user-exec.c b/user-exec.c
index 26cde7c..718c54f 100644
--- a/user-exec.c
+++ b/user-exec.c
@@ -94,6 +94,12 @@ static inline int handle_cpu_signal(uintptr_t pc, unsigned long address,
         return 1;
     }
 
+    if (GUEST_BASE) {
+        /* Convert forcefully to guest address space, invalid addresses
+           are still valid segv ones */
+        address = address - GUEST_BASE;
+    }
+
     env = current_cpu->env_ptr;
     /* see if it is an MMU fault */
     ret = cpu_handle_mmu_fault(env, address, is_write, MMU_USER_IDX);
-- 
1.6.0.2