Hi Christophe, On Fri, Jul 2, 2021 at 10:16 PM Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx> wrote: > Commit: c742199a014de23ee92055c2473d91fe5561ffdf > Parent: 79c1c594f49a88fba9744cb5c85978c6b1b365ec > Refname: refs/heads/master > Web: https://git.kernel.org/torvalds/c/c742199a014de23ee92055c2473d91fe5561ffdf > Author: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > AuthorDate: Wed Jun 30 18:48:03 2021 -0700 > Committer: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > CommitDate: Wed Jun 30 20:47:26 2021 -0700 > > mm/pgtable: add stubs for {pmd/pub}_{set/clear}_huge > > For architectures with no PMD and/or no PUD, add stubs similar to what we > have for architectures without P4D. > > [christophe.leroy@xxxxxxxxxx: arm64: define only {pud/pmd}_{set/clear}_huge when useful] > Link: https://lkml.kernel.org/r/73ec95f40cafbbb69bdfb43a7f53876fd845b0ce.1620990479.git.christophe.leroy@xxxxxxxxxx > [christophe.leroy@xxxxxxxxxx: x86: define only {pud/pmd}_{set/clear}_huge when useful] > Link: https://lkml.kernel.org/r/7fbf1b6bc3e15c07c24fa45278d57064f14c896b.1620930415.git.christophe.leroy@xxxxxxxxxx > > Link: https://lkml.kernel.org/r/5ac5976419350e8e048d463a64cae449eb3ba4b0.1620795204.git.christophe.leroy@xxxxxxxxxx > Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> > Cc: Mike Rapoport <rppt@xxxxxxxxxx> > Cc: Nicholas Piggin <npiggin@xxxxxxxxx> > Cc: Paul Mackerras <paulus@xxxxxxxxx> > Cc: Uladzislau Rezki <uladzislau.rezki@xxxxxxxx> > Cc: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Since this commit, both WARN_ON() tests in pud_huge_tests() are triggering on arm64 if CONFIG_ARM64_VA_BITS_39=y and CONFIG_PGTABLE_LEVELS=3: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at mm/debug_vm_pgtable.c:438 debug_vm_pgtable+0x6d0/0x7c4 Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-salvator-x-00209-gc742199a014d #1068 Hardware name: Renesas Salvator-X 2nd version board based on r8a77951 (DT) pstate: a0400005 (NzCv daif +PAN -UAO -TCO BTYPE=--) pc : debug_vm_pgtable+0x6d0/0x7c4 lr : debug_vm_pgtable+0x6cc/0x7c4 sp : ffffffc0124cbd00 x29: ffffffc0124cbd00 x28: 0000000000000c30 x27: ffffff84c5e465a0 x26: ffffff84c5e46000 x25: ffffff84c5e42000 x24: 00000000000005a0 x23: ffffffc010c41000 x22: 0020000050cb0fc3 x21: ffffff84c5e45ed0 x20: ffffff84c27470a8 x19: ffffff84c2747040 x18: 0000000000000cc0 x17: 00000000b2491cf5 x16: 0000000000000014 x15: 0000000000000000 x14: 0000000000000002 x13: 00000000000b56dd x12: 0000000000000901 x11: ffffffc01116d040 x10: 00000000000038e4 x9 : 00000000ffffffff x8 : 0000000000000000 x7 : ffffffc010cc4cd0 x6 : 0000000000000000 x5 : 000000000004028e x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffffff84c08bc040 Call trace: debug_vm_pgtable+0x6d0/0x7c4 do_one_initcall+0xec/0x278 kernel_init_freeable+0x220/0x224 kernel_init+0x10/0x108 ret_from_fork+0x10/0x18 irq event stamp: 1062694 hardirqs last enabled at (1062693): [<ffffffc0101bb030>] free_unref_page+0x120/0x138 hardirqs last disabled at (1062694): [<ffffffc01085f31c>] el1_dbg+0x24/0x4c softirqs last enabled at (1062636): [<ffffffc0100101c8>] _stext+0x1c8/0x43c softirqs last disabled at (1062627): [<ffffffc010080020>] __irq_exit_rcu+0xdc/0x124 ---[ end trace 864024bcea12ea00 ]--- ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at mm/debug_vm_pgtable.c:439 debug_vm_pgtable+0x6d4/0x7c4 Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 5.13.0-salvator-x-00209-gc742199a014d #1068 Hardware name: Renesas Salvator-X 2nd version board based on r8a77951 (DT) pstate: a0400005 (NzCv daif +PAN -UAO -TCO BTYPE=--) pc : debug_vm_pgtable+0x6d4/0x7c4 lr : debug_vm_pgtable+0x6cc/0x7c4 sp : ffffffc0124cbd00 x29: ffffffc0124cbd00 x28: 0000000000000c30 x27: ffffff84c5e465a0 x26: ffffff84c5e46000 x25: ffffff84c5e42000 x24: 00000000000005a0 x23: ffffffc010c41000 x22: 0020000050cb0fc3 x21: ffffff84c5e45ed0 x20: ffffff84c27470a8 x19: ffffff84c2747040 x18: 0000000000000cc0 x17: 00000000b2491cf5 x16: 0000000000000014 x15: 0000000000000000 x14: 0000000000000002 x13: 00000000000b56dd x12: 0000000000000901 x11: ffffffc01116d040 x10: 00000000000038e4 x9 : 00000000ffffffff x8 : 0000000000000000 x7 : ffffffc010cc4cd0 x6 : 0000000000000000 x5 : 000000000004028e x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffffff84c08bc040 Call trace: debug_vm_pgtable+0x6d4/0x7c4 do_one_initcall+0xec/0x278 kernel_init_freeable+0x220/0x224 kernel_init+0x10/0x108 ret_from_fork+0x10/0x18 irq event stamp: 1062706 hardirqs last enabled at (1062705): [<ffffffc01085ef80>] exit_to_kernel_mode+0xf0/0x100 hardirqs last disabled at (1062706): [<ffffffc01085f31c>] el1_dbg+0x24/0x4c softirqs last enabled at (1062704): [<ffffffc0100101c8>] _stext+0x1c8/0x43c softirqs last disabled at (1062697): [<ffffffc010080020>] __irq_exit_rcu+0xdc/0x124 ---[ end trace 864024bcea12ea01 ]--- Switching to CONFIG_ARM64_VA_BITS_48=y and CONFIG_PGTABLE_LEVELS=4 makes the warning disappear. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
