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Date:   Tue, 23 Mar 2021 13:39:40 -0700
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Subject: [PATCH v3 11/17] psci: use __pa_function for cpu_resume
From:   Sami Tolvanen <samitolvanen@google.com>
To:     Kees Cook <keescook@chromium.org>
Cc:     Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Will Deacon <will@kernel.org>, Jessica Yu <jeyu@kernel.org>,
        Arnd Bergmann <arnd@arndb.de>, Tejun Heo <tj@kernel.org>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Christoph Hellwig <hch@infradead.org>,
        Peter Zijlstra <peterz@infradead.org>, bpf@vger.kernel.org,
        linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
        Sami Tolvanen <samitolvanen@google.com>
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With CONFIG_CFI_CLANG, the compiler replaces function pointers with
jump table addresses, which results in __pa_symbol returning the
physical address of the jump table entry. As the jump table contains
an immediate jump to an EL1 virtual address, this typically won't
work as intended. Use __pa_function instead to get the address to
cpu_resume.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
---
 drivers/firmware/psci/psci.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index f5fc429cae3f..facd3cce3244 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -326,7 +326,7 @@ static int psci_suspend_finisher(unsigned long state)
 {
 	u32 power_state = state;
 
-	return psci_ops.cpu_suspend(power_state, __pa_symbol(cpu_resume));
+	return psci_ops.cpu_suspend(power_state, __pa_function(cpu_resume));
 }
 
 int psci_cpu_suspend_enter(u32 state)
@@ -345,7 +345,7 @@ int psci_cpu_suspend_enter(u32 state)
 static int psci_system_suspend(unsigned long unused)
 {
 	return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
-			      __pa_symbol(cpu_resume), 0, 0);
+			      __pa_function(cpu_resume), 0, 0);
 }
 
 static int psci_system_suspend_enter(suspend_state_t state)
-- 
2.31.0.291.g576ba9dcdaf-goog