This is a note to let you know that I've just added the patch titled
LoongArch/smp: Call rcutree_report_cpu_starting() at tlb_init()
to the 6.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
loongarch-smp-call-rcutree_report_cpu_starting-at-tl.patch
and it can be found in the queue-6.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c2d61000454daa06a6a1a6ce8f4ce10272d5d328
Author: Huacai Chen <chenhuacai@xxxxxxxxxx>
Date: Fri Jan 26 16:22:07 2024 +0800
LoongArch/smp: Call rcutree_report_cpu_starting() at tlb_init()
[ Upstream commit 5056c596c3d1848021a4eaa76ee42f4c05c50346 ]
Machines which have more than 8 nodes fail to boot SMP after commit
a2ccf46333d7b2cf96 ("LoongArch/smp: Call rcutree_report_cpu_starting()
earlier"). Because such machines use tlb-based per-cpu base address
rather than dmw-based per-cpu base address, resulting per-cpu variables
can only be accessed after tlb_init(). But rcutree_report_cpu_starting()
is now called before tlb_init() and accesses per-cpu variables indeed.
Since the original patch want to avoid the lockdep warning caused by
page allocation in tlb_init(), we can move rcutree_report_cpu_starting()
to tlb_init() where after tlb exception configuration but before page
allocation.
Fixes: a2ccf46333d7b2cf96 ("LoongArch/smp: Call rcutree_report_cpu_starting() earlier")
Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/loongarch/kernel/smp.c b/arch/loongarch/kernel/smp.c
index 5bca12d16e06..2fbf541d7b4f 100644
--- a/arch/loongarch/kernel/smp.c
+++ b/arch/loongarch/kernel/smp.c
@@ -506,7 +506,6 @@ asmlinkage void start_secondary(void)
sync_counter();
cpu = raw_smp_processor_id();
set_my_cpu_offset(per_cpu_offset(cpu));
- rcutree_report_cpu_starting(cpu);
cpu_probe();
constant_clockevent_init();
diff --git a/arch/loongarch/mm/tlb.c b/arch/loongarch/mm/tlb.c
index 2c0a411f23aa..0b95d32b30c9 100644
--- a/arch/loongarch/mm/tlb.c
+++ b/arch/loongarch/mm/tlb.c
@@ -284,12 +284,16 @@ static void setup_tlb_handler(int cpu)
set_handler(EXCCODE_TLBNR * VECSIZE, handle_tlb_protect, VECSIZE);
set_handler(EXCCODE_TLBNX * VECSIZE, handle_tlb_protect, VECSIZE);
set_handler(EXCCODE_TLBPE * VECSIZE, handle_tlb_protect, VECSIZE);
- }
+ } else {
+ int vec_sz __maybe_unused;
+ void *addr __maybe_unused;
+ struct page *page __maybe_unused;
+
+ /* Avoid lockdep warning */
+ rcutree_report_cpu_starting(cpu);
+
#ifdef CONFIG_NUMA
- else {
- void *addr;
- struct page *page;
- const int vec_sz = sizeof(exception_handlers);
+ vec_sz = sizeof(exception_handlers);
if (pcpu_handlers[cpu])
return;
@@ -305,8 +309,8 @@ static void setup_tlb_handler(int cpu)
csr_write64(pcpu_handlers[cpu], LOONGARCH_CSR_EENTRY);
csr_write64(pcpu_handlers[cpu], LOONGARCH_CSR_MERRENTRY);
csr_write64(pcpu_handlers[cpu] + 80*VECSIZE, LOONGARCH_CSR_TLBRENTRY);
- }
#endif
+ }
}
void tlb_init(int cpu)
