mm/page_alloc: change all pageblocks migrate type on coalescing

When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug #431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug #431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1c4cde ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 822e05f1a9646b7a3992301fdeb3e7f41fd0946f..f6586f165b8936f334e70059e0b2301ee53b7177 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -914,6 +914,17 @@ buddy_merge_likely(unsigned long pfn, unsigned long buddy_pfn,
                        NULL) != NULL;
 }
 
+static void change_pageblock_range(struct page *pageblock_page,
+                                  int start_order, int migratetype)
+{
+       int nr_pageblocks = 1 << (start_order - pageblock_order);
+
+       while (nr_pageblocks--) {
+               set_pageblock_migratetype(pageblock_page, migratetype);
+               pageblock_page += pageblock_nr_pages;
+       }
+}
+
 /*
  * Freeing function for a buddy system allocator.
  *
@@ -1000,7 +1011,7 @@ static inline void __free_one_page(struct page *page,
                         * expand() down the line puts the sub-blocks
                         * on the right freelists.
                         */
-                       set_pageblock_migratetype(buddy, migratetype);
+                       change_pageblock_range(buddy, order, migratetype);
                }
 
                combined_pfn = buddy_pfn & pfn;
@@ -2147,17 +2158,6 @@ bool pageblock_unisolate_and_move_free_pages(struct zone *zone, struct page *pag
 
 #endif /* CONFIG_MEMORY_ISOLATION */
 
-static void change_pageblock_range(struct page *pageblock_page,
-                                       int start_order, int migratetype)
-{
-       int nr_pageblocks = 1 << (start_order - pageblock_order);
-
-       while (nr_pageblocks--) {
-               set_pageblock_migratetype(pageblock_page, migratetype);
-               pageblock_page += pageblock_nr_pages;
-       }
-}
-
 static inline bool boost_watermark(struct zone *zone)
 {
        unsigned long max_boost;