generic: 5.15: move MIPS cpuinfo patch from pending to backport

Move MIPS cpuinfo patch from pending to backport as it got merged
upstream.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.15/330-v5.16-02-MIPS-Fix-using-smp_processor_id-in-preemptible-in-sh.patch b/target/linux/generic/backport-5.15/330-v5.16-02-MIPS-Fix-using-smp_processor_id-in-preemptible-in-sh.patch
new file mode 100644
index 0000000000..6caf7d06d4
--- /dev/null
+++ b/target/linux/generic/backport-5.15/330-v5.16-02-MIPS-Fix-using-smp_processor_id-in-preemptible-in-sh.patch
@@ -0,0 +1,62 @@
+From 1cab5bd69eb1f995ced2d7576cb15f8a8941fd85 Mon Sep 17 00:00:00 2001
+From: Tiezhu Yang <yangtiezhu@loongson.cn>
+Date: Thu, 25 Nov 2021 19:39:32 +0800
+Subject: [PATCH 1/1] MIPS: Fix using smp_processor_id() in preemptible in
+ show_cpuinfo()
+
+There exists the following issue under DEBUG_PREEMPT:
+
+ BUG: using smp_processor_id() in preemptible [00000000] code: systemd/1
+ caller is show_cpuinfo+0x460/0xea0
+ ...
+ Call Trace:
+ [<ffffffff8020f0dc>] show_stack+0x94/0x128
+ [<ffffffff80e6cab4>] dump_stack_lvl+0x94/0xd8
+ [<ffffffff80e74c5c>] check_preemption_disabled+0x104/0x110
+ [<ffffffff802209c8>] show_cpuinfo+0x460/0xea0
+ [<ffffffff80539d54>] seq_read_iter+0xfc/0x4f8
+ [<ffffffff804fcc10>] new_sync_read+0x110/0x1b8
+ [<ffffffff804ff57c>] vfs_read+0x1b4/0x1d0
+ [<ffffffff804ffb18>] ksys_read+0xd0/0x110
+ [<ffffffff8021c090>] syscall_common+0x34/0x58
+
+We can see the following call trace:
+ show_cpuinfo()
+   cpu_has_fpu
+     current_cpu_data
+       smp_processor_id()
+
+ $ addr2line -f -e vmlinux 0xffffffff802209c8
+ show_cpuinfo
+ arch/mips/kernel/proc.c:188
+
+ $ head -188 arch/mips/kernel/proc.c | tail -1
+	 if (cpu_has_fpu)
+
+ arch/mips/include/asm/cpu-features.h
+ #  define cpu_has_fpu		(current_cpu_data.options & MIPS_CPU_FPU)
+
+ arch/mips/include/asm/cpu-info.h
+ #define current_cpu_data cpu_data[smp_processor_id()]
+
+Based on the above analysis, fix the issue by using raw_cpu_has_fpu
+which calls raw_smp_processor_id() in show_cpuinfo().
+
+Fixes: 626bfa037299 ("MIPS: kernel: proc: add CPU option reporting")
+Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
+Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
+---
+ arch/mips/kernel/proc.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/arch/mips/kernel/proc.c
++++ b/arch/mips/kernel/proc.c
+@@ -166,7 +166,7 @@ static int show_cpuinfo(struct seq_file
+ 		seq_puts(m, " tx39_cache");
+ 	if (cpu_has_octeon_cache)
+ 		seq_puts(m, " octeon_cache");
+-	if (cpu_has_fpu)
++	if (raw_cpu_has_fpu)
+ 		seq_puts(m, " fpu");
+ 	if (cpu_has_32fpr)
+ 		seq_puts(m, " 32fpr");