Merge tag 'mips_fixes_5.5_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS fixes from Paul Burton:
 "A collection of MIPS fixes:

   - Fill the struct cacheinfo shared_cpu_map field with sensible
     values, notably avoiding issues with perf which was unhappy in the
     absence of these values.

   - A boot fix for Loongson 2E & 2F machines which was fallout from
     some refactoring performed this cycle.

   - A Kconfig dependency fix for the Loongson CPU HWMon driver.

   - A couple of VDSO fixes, ensuring gettimeofday() behaves
     appropriately for kernel configurations that don't include support
     for a clocksource the VDSO can use & fixing the calling convention
     for the n32 & n64 VDSOs which would previously clobber the $gp/$28
     register.

   - A build fix for vmlinuz compressed images which were
     inappropriately building with -fsanitize-coverage despite not being
     part of the kernel proper, then failing to link due to the missing
     __sanitizer_cov_trace_pc() function.

   - A couple of eBPF JIT fixes, including disabling it for MIPS32 due
     to a large number of issues with the code generated there &
     reflecting ISA dependencies in Kconfig to enforce that systems
     which don't support the JIT must include the interpreter"

* tag 'mips_fixes_5.5_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: Avoid VDSO ABI breakage due to global register variable
  MIPS: BPF: eBPF JIT: check for MIPS ISA compliance in Kconfig
  MIPS: BPF: Disable MIPS32 eBPF JIT
  MIPS: Prevent link failure with kcov instrumentation
  MIPS: Kconfig: Use correct form for 'depends on'
  mips: Fix gettimeofday() in the vdso library
  MIPS: Fix boot on Fuloong2 systems
  mips: cacheinfo: report shared CPU map

3 files changed, 21 insertions, 15 deletions

diff --git a/arch/mips/include/asm/cpu-type.h b/arch/mips/include/asm/cpu-type.h
index c46c59b0f1b4..49f0061a6051 100644
--- a/arch/mips/include/asm/cpu-type.h
+++ b/arch/mips/include/asm/cpu-type.h
@@ -15,7 +15,8 @@
 static inline int __pure __get_cpu_type(const int cpu_type)
 {
 	switch (cpu_type) {
-#if defined(CONFIG_SYS_HAS_CPU_LOONGSON2EF)
+#if defined(CONFIG_SYS_HAS_CPU_LOONGSON2E) || \
+    defined(CONFIG_SYS_HAS_CPU_LOONGSON2F)
 	case CPU_LOONGSON2EF:
 #endif
 
diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h
index 4993db40482c..ee26f9a4575d 100644
--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -49,8 +49,26 @@ struct thread_info {
 	.addr_limit	= KERNEL_DS,		\
 }
 
-/* How to get the thread information struct from C.  */
+/*
+ * A pointer to the struct thread_info for the currently executing thread is
+ * held in register $28/$gp.
+ *
+ * We declare __current_thread_info as a global register variable rather than a
+ * local register variable within current_thread_info() because clang doesn't
+ * support explicit local register variables.
+ *
+ * When building the VDSO we take care not to declare the global register
+ * variable because this causes GCC to not preserve the value of $28/$gp in
+ * functions that change its value (which is common in the PIC VDSO when
+ * accessing the GOT). Since the VDSO shouldn't be accessing
+ * __current_thread_info anyway we declare it extern in order to cause a link
+ * failure if it's referenced.
+ */
+#ifdef __VDSO__
+extern struct thread_info *__current_thread_info;
+#else
 register struct thread_info *__current_thread_info __asm__("$28");
+#endif
 
 static inline struct thread_info *current_thread_info(void)
 {
diff --git a/arch/mips/include/asm/vdso/gettimeofday.h b/arch/mips/include/asm/vdso/gettimeofday.h
index b08825531e9f..0ae9b4cbc153 100644
--- a/arch/mips/include/asm/vdso/gettimeofday.h
+++ b/arch/mips/include/asm/vdso/gettimeofday.h
@@ -26,8 +26,6 @@
 
 #define __VDSO_USE_SYSCALL		ULLONG_MAX
 
-#ifdef CONFIG_MIPS_CLOCK_VSYSCALL
-
 static __always_inline long gettimeofday_fallback(
 				struct __kernel_old_timeval *_tv,
 				struct timezone *_tz)
@@ -48,17 +46,6 @@ static __always_inline long gettimeofday_fallback(
 	return error ? -ret : ret;
 }
 
-#else
-
-static __always_inline long gettimeofday_fallback(
-				struct __kernel_old_timeval *_tv,
-				struct timezone *_tz)
-{
-	return -1;
-}
-
-#endif
-
 static __always_inline long clock_gettime_fallback(
 					clockid_t _clkid,
 					struct __kernel_timespec *_ts)