path: root/sys
diff options
authorBrandon Bergren <bdragon@FreeBSD.org>2021-02-07 22:05:41 +0000
committerBrandon Bergren <bdragon@FreeBSD.org>2021-02-07 22:13:55 +0000
commitd26f2a50ff48dacd38ba358d658882d51f7bdbc4 (patch)
tree0be12e3eed138bebda8d7ee89cbd35dd0f3cfa48 /sys
parente44a78ce6f249f1eb7df94cb6953698953ebd88b (diff)
powerpc64: Fix boot on virtual-mode OF (PowerMac G5)
In 78599c32efed3247d165302a1fbe8d9203e38974, CFI endproc decoration was added to locore64.S. However, it missed the subtle detail that __restartkernel_virtual() falls through to __restartkernel(). This was causing boot failure on PowerMac G5, as it tried to execute the epilogue as code. Fix this by branching to __restartkernel() instead of intentionally running off the end of the function. While here, add some additional notes on how the virtual mode restart works. MFC after: 3 days
Diffstat (limited to 'sys')
1 files changed, 10 insertions, 0 deletions
diff --git a/sys/powerpc/aim/locore64.S b/sys/powerpc/aim/locore64.S
index 0bc0619620d9..f0a183c4b331 100644
--- a/sys/powerpc/aim/locore64.S
+++ b/sys/powerpc/aim/locore64.S
@@ -255,6 +255,16 @@ ASENTRY_NOPROF(__restartkernel_virtual)
addi %r14, %r14, 1
cmpdi %r14, 16
blt 1b
+ /*
+ * Now that we are set up with a temporary direct map, we can
+ * continue with __restartkernel. Translation will be switched
+ * back on at the rfid, at which point we will be executing from
+ * the temporary direct map we just installed, until the kernel
+ * takes over responsibility for the MMU.
+ */
+ bl __restartkernel
+ nop