Re: [PATCH v2 4/5] mm/page_alloc: place pages to tail in __free_pages_core()

[Sean Anderson <sean.anderson@xxxxxxxx>]

Hi David,

This patch breaks booting on my custom Xilinx ZynqMP board. Booting
fails just after/during GIC initialization:

[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd034]
[    0.000000] Linux version 5.14.0 (sean@plantagenet) (aarch64-linux-gnu-gcc 
(Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0, GNU ld (GNU Binutils for Ubuntu) 2.34) 
#251 SMP Tue Sep 7 18:11:50 EDT 2021
[    0.000000] Machine model: xlnx,zynqmp
[    0.000000] earlycon: cdns0 at MMIO 0x00000000ff010000 (options '115200n8')
[    0.000000] printk: bootconsole [cdns0] enabled
[    0.000000] efi: UEFI not found.
[    0.000000] Zone ranges:
[    0.000000]   DMA32    [mem 0x0000000000000000-0x00000000ffffffff]
[    0.000000]   Normal   [mem 0x0000000100000000-0x000000087fffffff]
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000000000000-0x000000007fefffff]
[    0.000000]   node   0: [mem 0x0000000800000000-0x000000087fffffff]
[    0.000000] Initmem setup node 0 [mem 0x0000000000000000-0x000000087fffffff]
[    0.000000] On node 0, zone Normal: 256 pages in unavailable ranges
[    0.000000] cma: Reserved 1000 MiB at 0x0000000041400000
[    0.000000] psci: probing for conduit method from DT.
[    0.000000] psci: PSCIv1.1 detected in firmware.
[    0.000000] psci: Using standard PSCI v0.2 function IDs
[    0.000000] psci: MIGRATE_INFO_TYPE not supported.
[    0.000000] psci: SMC Calling Convention v1.1
[    0.000000] percpu: Embedded 19 pages/cpu s46752 r0 d31072 u77824
[    0.000000] Detected VIPT I-cache on CPU0
[    0.000000] CPU features: detected: ARM erratum 845719
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 1033987
[    0.000000] Kernel command line: earlycon clk_ignore_unused 
root=/dev/mmcblk0p2 rootwait rw cma=1000M
[    0.000000] Dentry cache hash table entries: 524288 (order: 10, 4194304 
bytes, linear)
[    0.000000] Inode-cache hash table entries: 262144 (order: 9, 2097152 bytes, 
linear)
[    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[    0.000000] software IO TLB: mapped [mem 
0x000000003d400000-0x0000000041400000] (64MB)
[    0.000000] Memory: 3023384K/4193280K available (4288K kernel code, 514K 
rwdata, 1200K rodata, 896K init, 187K bss, 145896K reserved, 1024000K 
cma-reserved)
[    0.000000] rcu: Hierarchical RCU implementation.
[    0.000000] rcu:     RCU event tracing is enabled.
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 
jiffies.
[    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000] GIC: Adjusting CPU interface base to 0x00000000f902f000
[    0.000000] Root IRQ handler: gic_handle_irq
[    0.000000] GIC: Using split EOI/Deactivate mode

and I bisected it to this patch. Applying the following patch (for 5.14)
fixes booting again:

---
 mm/page_alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index eeb3a9cb36bb..d4317392cadb 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1688,7 +1688,7 @@ void __free_pages_core(struct page *page, unsigned int 
order)
         * Bypass PCP and place fresh pages right to the tail, primarily
         * relevant for memory onlining.
         */
-       __free_pages_ok(page, order, FPI_TO_TAIL | FPI_SKIP_KASAN_POISON);
+       __free_pages_ok(page, order, FPI_NONE);
 }

 #ifdef CONFIG_NUMA
--
2.25.1

I have attached my config; but note that it lacks any storage drivers to
make bisecting easier.

--Sean

Attachment: .config
Description: Text document