FAILED: patch "[PATCH] LoongArch/smp: Call rcutree_report_cpu_starting() at" failed to apply to 6.1-stable tree

The patch below does not apply to the 6.1-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 <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 5056c596c3d1848021a4eaa76ee42f4c05c50346
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2024012911-outright-violin-e677@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

5056c596c3d1 ("LoongArch/smp: Call rcutree_report_cpu_starting() at tlb_init()")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 5056c596c3d1848021a4eaa76ee42f4c05c50346 Mon Sep 17 00:00:00 2001
From: Huacai Chen <[email protected]>
Date: Fri, 26 Jan 2024 16:22:07 +0800
Subject: [PATCH] LoongArch/smp: Call rcutree_report_cpu_starting() at
tlb_init()

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 <[email protected]>

arch/loongarch/kernel/smp.c +0 -1

index a16e3dbe9f09..2b49d30eb7c0 100644
@@ -509,7 +509,6 @@ 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();

arch/loongarch/mm/tlb.c +10 -6

index 2c0a411f23aa..0b95d32b30c9 100644
@@ -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)

Hi, Greg,

Quoted 16 lines · On Tue, Jan 30, 2024 at 12:53 AM <[email protected]> wrote:

The patch below does not apply to the 6.1-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 <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 5056c596c3d1848021a4eaa76ee42f4c05c50346
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2024012911-outright-violin-e677@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Quoted 3 lines

Possible dependencies:

5056c596c3d1 ("LoongArch/smp: Call rcutree_report_cpu_starting() at tlb_init()")

Similar to the commit which it fixes, please change rcutree_report_cpu_starting() to rcu_cpu_starting() in the code.

Quoted 19 lines · Huacai Chen

Hi, Greg,

Quoted 16 lines · On Tue, Jan 30, 2024 at 12:53 AM <[email protected]> wrote:

The patch below does not apply to the 6.1-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 <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 5056c596c3d1848021a4eaa76ee42f4c05c50346
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2024012911-outright-violin-e677@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Quoted 5 lines

Quoted 3 lines

Possible dependencies:

5056c596c3d1 ("LoongArch/smp: Call rcutree_report_cpu_starting() at tlb_init()")

Similar to the commit which it fixes, please change rcutree_report_cpu_starting() to rcu_cpu_starting() in the code.

I need a backported patch for that please :)