From 675bceb097e6fb9769309093ec6f3d33a2fed9cc Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 2 Sep 2020 09:31:22 +0530 Subject: [PATCH] powerpc/mm: Remove DEBUG_VM_PGTABLE support on powerpc The test is broken w.r.t page table update rules and results in kernel crash as below. Disable the support until we get the tests updated. [ 21.083519] kernel BUG at arch/powerpc/mm/pgtable.c:304! cpu 0x0: Vector: 700 (Program Check) at [c000000c6d1e76c0] pc: c00000000009a5ec: assert_pte_locked+0x14c/0x380 lr: c0000000005eeeec: pte_update+0x11c/0x190 sp: c000000c6d1e7950 msr: 8000000002029033 current = 0xc000000c6d172c80 paca = 0xc000000003ba0000 irqmask: 0x03 irq_happened: 0x01 pid = 1, comm = swapper/0 kernel BUG at arch/powerpc/mm/pgtable.c:304! [link register ] c0000000005eeeec pte_update+0x11c/0x190 [c000000c6d1e7950] 0000000000000001 (unreliable) [c000000c6d1e79b0] c0000000005eee14 pte_update+0x44/0x190 [c000000c6d1e7a10] c000000001a2ca9c pte_advanced_tests+0x160/0x3d8 [c000000c6d1e7ab0] c000000001a2d4fc debug_vm_pgtable+0x7e8/0x1338 [c000000c6d1e7ba0] c0000000000116ec do_one_initcall+0xac/0x5f0 [c000000c6d1e7c80] c0000000019e4fac kernel_init_freeable+0x4dc/0x5a4 [c000000c6d1e7db0] c000000000012474 kernel_init+0x24/0x160 [c000000c6d1e7e20] c00000000000cbd0 ret_from_kernel_thread+0x5c/0x6c With DEBUG_VM disabled [ 20.530152] BUG: Kernel NULL pointer dereference on read at 0x00000000 [ 20.530183] Faulting instruction address: 0xc0000000000df330 cpu 0x33: Vector: 380 (Data SLB Access) at [c000000c6d19f700] pc: c0000000000df330: memset+0x68/0x104 lr: c00000000009f6d8: hash__pmdp_huge_get_and_clear+0xe8/0x1b0 sp: c000000c6d19f990 msr: 8000000002009033 dar: 0 current = 0xc000000c6d177480 paca = 0xc00000001ec4f400 irqmask: 0x03 irq_happened: 0x01 pid = 1, comm = swapper/0 [link register ] c00000000009f6d8 hash__pmdp_huge_get_and_clear+0xe8/0x1b0 [c000000c6d19f990] c00000000009f748 hash__pmdp_huge_get_and_clear+0x158/0x1b0 (unreliable) [c000000c6d19fa10] c0000000019ebf30 pmd_advanced_tests+0x1f0/0x378 [c000000c6d19fab0] c0000000019ed088 debug_vm_pgtable+0x79c/0x1244 [c000000c6d19fba0] c0000000000116ec do_one_initcall+0xac/0x5f0 [c000000c6d19fc80] c0000000019a4fac kernel_init_freeable+0x4dc/0x5a4 [c000000c6d19fdb0] c000000000012474 kernel_init+0x24/0x160 [c000000c6d19fe20] c00000000000cbd0 ret_from_kernel_thread+0x5c/0x6c 33:mon> Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200902040122.136414-1-aneesh.kumar@linux.ibm.com --- Documentation/features/debug/debug-vm-pgtable/arch-support.txt | 2 +- arch/powerpc/Kconfig | 1 - 2 files changed, 1 insertion(+), 2 deletions(-) diff --git a/Documentation/features/debug/debug-vm-pgtable/arch-support.txt b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt index 53da483c8326..1c49723e7534 100644 --- a/Documentation/features/debug/debug-vm-pgtable/arch-support.txt +++ b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt @@ -22,7 +22,7 @@ | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | - | powerpc: | ok | + | powerpc: | TODO | | riscv: | ok | | s390: | ok | | sh: | TODO | diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 65bed1fdeaad..787e829b6f25 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -116,7 +116,6 @@ config PPC # select ARCH_32BIT_OFF_T if PPC32 select ARCH_HAS_DEBUG_VIRTUAL - select ARCH_HAS_DEBUG_VM_PGTABLE select ARCH_HAS_DEVMEM_IS_ALLOWED select ARCH_HAS_ELF_RANDOMIZE select ARCH_HAS_FORTIFY_SOURCE