The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 897bc3df8c5aebb54c32d831f917592e873d0559 Mon Sep 17 00:00:00 2001
From: Breno Leitao <leitao@xxxxxxxxxx>
Date: Wed, 9 Jan 2019 11:16:45 -0200
Subject: [PATCH] powerpc/tm: Limit TM code inside PPC_TRANSACTIONAL_MEM
Commit e1c3743e1a20 ("powerpc/tm: Set MSR[TS] just prior to recheckpoint")
moved a code block around and this block uses a 'msr' variable outside of
the CONFIG_PPC_TRANSACTIONAL_MEM, however the 'msr' variable is declared
inside a CONFIG_PPC_TRANSACTIONAL_MEM block, causing a possible error when
CONFIG_PPC_TRANSACTION_MEM is not defined.
error: 'msr' undeclared (first use in this function)
This is not causing a compilation error in the mainline kernel, because
'msr' is being used as an argument of MSR_TM_ACTIVE(), which is defined as
the following when CONFIG_PPC_TRANSACTIONAL_MEM is *not* set:
#define MSR_TM_ACTIVE(x) 0
This patch just fixes this issue avoiding the 'msr' variable usage outside
the CONFIG_PPC_TRANSACTIONAL_MEM block, avoiding trusting in the
MSR_TM_ACTIVE() definition.
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Christoph Biedl <linux-kernel.bfrz@xxxxxxxxxxxxxxxxxx>
Fixes: e1c3743e1a20 ("powerpc/tm: Set MSR[TS] just prior to recheckpoint")
Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index bd5e6834ca69..6794466f6420 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -755,11 +755,12 @@ SYSCALL_DEFINE0(rt_sigreturn)
if (restore_tm_sigcontexts(current, &uc->uc_mcontext,
&uc_transact->uc_mcontext))
goto badframe;
- }
+ } else
#endif
- /* Fall through, for non-TM restore */
- if (!MSR_TM_ACTIVE(msr)) {
+ {
/*
+ * Fall through, for non-TM restore
+ *
* Unset MSR[TS] on the thread regs since MSR from user
* context does not have MSR active, and recheckpoint was
* not called since restore_tm_sigcontexts() was not called
