From f14040bca89258b8a1c71e2112e430462172ce93 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Thu, 13 Sep 2018 15:33:47 +1000 Subject: [PATCH 01/14] KVM: PPC: Book3S HV: Fix guest r11 corruption with POWER9 TM workarounds When we come into the softpatch handler (0x1500), we use r11 to store the HSRR0 for later use by the denorm handler. We also use the softpatch handler for the TM workarounds for POWER9. Unfortunately, in kvmppc_interrupt_hv we later store r11 out to the vcpu assuming it's still what we got from userspace. This causes r11 to be corrupted in the VCPU and hence when we restore the guest, we get a corrupted r11. We've seen this when running TM tests inside guests on P9. This fixes the problem by only touching r11 in the denorm case. Fixes: 4bb3c7a020 ("KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9") Cc: # 4.17+ Test-by: Suraj Jitindar Singh Reviewed-by: Paul Mackerras Signed-off-by: Michael Neuling Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/exceptions-64s.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index ea04dfb8c0927..2d8fc8c9da7a1 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -1314,9 +1314,7 @@ EXC_REAL_BEGIN(denorm_exception_hv, 0x1500, 0x100) #ifdef CONFIG_PPC_DENORMALISATION mfspr r10,SPRN_HSRR1 - mfspr r11,SPRN_HSRR0 /* save HSRR0 */ andis. r10,r10,(HSRR1_DENORM)@h /* denorm? */ - addi r11,r11,-4 /* HSRR0 is next instruction */ bne+ denorm_assist #endif @@ -1382,6 +1380,8 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S) */ XVCPSGNDP32(32) denorm_done: + mfspr r11,SPRN_HSRR0 + subi r11,r11,4 mtspr SPRN_HSRR0,r11 mtcrf 0x80,r9 ld r9,PACA_EXGEN+EX_R9(r13) From 51c3c62b58b357e8d35e4cc32f7b4ec907426fe3 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 14 Sep 2018 11:14:11 +1000 Subject: [PATCH 02/14] powerpc: Avoid code patching freed init sections This stops us from doing code patching in init sections after they've been freed. In this chain: kvm_guest_init() -> kvm_use_magic_page() -> fault_in_pages_readable() -> __get_user() -> __get_user_nocheck() -> barrier_nospec(); We have a code patching location at barrier_nospec() and kvm_guest_init() is an init function. This whole chain gets inlined, so when we free the init section (hence kvm_guest_init()), this code goes away and hence should no longer be patched. We seen this as userspace memory corruption when using a memory checker while doing partition migration testing on powervm (this starts the code patching post migration via /sys/kernel/mobility/migration). In theory, it could also happen when using /sys/kernel/debug/powerpc/barrier_nospec. Cc: stable@vger.kernel.org # 4.13+ Signed-off-by: Michael Neuling Reviewed-by: Nicholas Piggin Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/setup.h | 1 + arch/powerpc/lib/code-patching.c | 6 ++++++ arch/powerpc/mm/mem.c | 2 ++ 3 files changed, 9 insertions(+) diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h index 1a951b00465d7..1fffbba8d6a5e 100644 --- a/arch/powerpc/include/asm/setup.h +++ b/arch/powerpc/include/asm/setup.h @@ -9,6 +9,7 @@ extern void ppc_printk_progress(char *s, unsigned short hex); extern unsigned int rtas_data; extern unsigned long long memory_limit; +extern bool init_mem_is_free; extern unsigned long klimit; extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask); diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 850f3b8f4da5e..6ae2777c220d4 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -28,6 +28,12 @@ static int __patch_instruction(unsigned int *exec_addr, unsigned int instr, { int err; + /* Make sure we aren't patching a freed init section */ + if (init_mem_is_free && init_section_contains(exec_addr, 4)) { + pr_debug("Skipping init section patching addr: 0x%px\n", exec_addr); + return 0; + } + __put_user_size(instr, patch_addr, 4, err); if (err) return err; diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 5c8530d0c6118..04ccb274a6205 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -63,6 +63,7 @@ #endif unsigned long long memory_limit; +bool init_mem_is_free; #ifdef CONFIG_HIGHMEM pte_t *kmap_pte; @@ -396,6 +397,7 @@ void free_initmem(void) { ppc_md.progress = ppc_printk_progress; mark_initmem_nx(); + init_mem_is_free = true; free_initmem_default(POISON_FREE_INITMEM); } From 7233b8cab39014620ac9534da11f0f3e506d8fd8 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Tue, 11 Sep 2018 15:38:05 +1000 Subject: [PATCH 03/14] powerpc/powernv/ioda2: Reduce upper limit for DMA window size (again) mpe: This was fixed originally in commit d3d4ffaae439 ("powerpc/powernv/ioda2: Reduce upper limit for DMA window size"), but contrary to what the merge commit says was inadvertently lost by me in commit ce57c6610cc2 ("Merge branch 'topic/ppc-kvm' into next") which brought in changes that moved the code to a new file. So reapply it to the new file. Original commit message follows: We use PHB in mode1 which uses bit 59 to select a correct DMA window. However there is mode2 which uses bits 59:55 and allows up to 32 DMA windows per a PE. Even though documentation does not clearly specify that, it seems that the actual hardware does not support bits 59:55 even in mode1, in other words we can create a window as big as 1<<58 but DMA simply won't work. This reduces the upper limit from 59 to 55 bits to let the userspace know about the hardware limits. Fixes: ce57c6610cc2 ("Merge branch 'topic/ppc-kvm' into next") Signed-off-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/powernv/pci-ioda-tce.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/powernv/pci-ioda-tce.c b/arch/powerpc/platforms/powernv/pci-ioda-tce.c index 6c5db1acbe8df..fe9691040f54c 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda-tce.c +++ b/arch/powerpc/platforms/powernv/pci-ioda-tce.c @@ -276,7 +276,7 @@ long pnv_pci_ioda2_table_alloc_pages(int nid, __u64 bus_offset, level_shift = entries_shift + 3; level_shift = max_t(unsigned int, level_shift, PAGE_SHIFT); - if ((level_shift - 3) * levels + page_shift >= 60) + if ((level_shift - 3) * levels + page_shift >= 55) return -EINVAL; /* Allocate TCE table */ From 85682a7e3b9c664995ad477520f917039afdc330 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 10 Sep 2018 06:09:04 +0000 Subject: [PATCH 04/14] powerpc: fix csum_ipv6_magic() on little endian platforms On little endian platforms, csum_ipv6_magic() keeps len and proto in CPU byte order. This generates a bad results leading to ICMPv6 packets from other hosts being dropped by powerpc64le platforms. In order to fix this, len and proto should be converted to network byte order ie bigendian byte order. However checksumming 0x12345678 and 0x56341278 provide the exact same result so it is enough to rotate the sum of len and proto by 1 byte. PPC32 only support bigendian so the fix is needed for PPC64 only Fixes: e9c4943a107b ("powerpc: Implement csum_ipv6_magic in assembly") Reported-by: Jianlin Shi Reported-by: Xin Long Cc: # 4.18+ Signed-off-by: Christophe Leroy Tested-by: Xin Long Signed-off-by: Michael Ellerman --- arch/powerpc/lib/checksum_64.S | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S index 886ed94b9c133..d05c8af4ac51f 100644 --- a/arch/powerpc/lib/checksum_64.S +++ b/arch/powerpc/lib/checksum_64.S @@ -443,6 +443,9 @@ _GLOBAL(csum_ipv6_magic) addc r0, r8, r9 ld r10, 0(r4) ld r11, 8(r4) +#ifdef CONFIG_CPU_LITTLE_ENDIAN + rotldi r5, r5, 8 +#endif adde r0, r0, r10 add r5, r5, r7 adde r0, r0, r11 From c716a25b9b70084e1144f77423f5aedd772ea478 Mon Sep 17 00:00:00 2001 From: Thiago Jung Bauermann Date: Thu, 20 Sep 2018 01:38:58 -0300 Subject: [PATCH 05/14] powerpc/pkeys: Fix reading of ibm, processor-storage-keys property scan_pkey_feature() uses of_property_read_u32_array() to read the ibm,processor-storage-keys property and calls be32_to_cpu() on the value it gets. The problem is that of_property_read_u32_array() already returns the value converted to the CPU byte order. The value of pkeys_total ends up more or less sane because there's a min() call in pkey_initialize() which reduces pkeys_total to 32. So in practice the kernel ignores the fact that the hypervisor reserved one key for itself (the device tree advertises 31 keys in my test VM). This is wrong, but the effect in practice is that when a process tries to allocate the 32nd key, it gets an -EINVAL error instead of -ENOSPC which would indicate that there aren't any keys available Fixes: cf43d3b26452 ("powerpc: Enable pkey subsystem") Cc: stable@vger.kernel.org # v4.16+ Signed-off-by: Thiago Jung Bauermann Signed-off-by: Michael Ellerman --- arch/powerpc/mm/pkeys.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c index 333b1f80c4354..b271b283c785e 100644 --- a/arch/powerpc/mm/pkeys.c +++ b/arch/powerpc/mm/pkeys.c @@ -45,7 +45,7 @@ static void scan_pkey_feature(void) * Since any pkey can be used for data or execute, we will just treat * all keys as equal and track them as one entity. */ - pkeys_total = be32_to_cpu(vals[0]); + pkeys_total = vals[0]; pkeys_devtree_defined = true; } From 8604895a34d92f5e186ceb931b0d1b384030ea3d Mon Sep 17 00:00:00 2001 From: Michael Bringmann Date: Thu, 20 Sep 2018 11:45:13 -0500 Subject: [PATCH 06/14] powerpc/pseries: Fix unitialized timer reset on migration After migration of a powerpc LPAR, the kernel executes code to update the system state to reflect new platform characteristics. Such changes include modifications to device tree properties provided to the system by PHYP. Property notifications received by the post_mobility_fixup() code are passed along to the kernel in general through a call to of_update_property() which in turn passes such events back to all modules through entries like the '.notifier_call' function within the NUMA module. When the NUMA module updates its state, it resets its event timer. If this occurs after a previous call to stop_topology_update() or on a system without VPHN enabled, the code runs into an unitialized timer structure and crashes. This patch adds a safety check along this path toward the problem code. An example crash log is as follows. ibmvscsi 30000081: Re-enabling adapter! ------------[ cut here ]------------ kernel BUG at kernel/time/timer.c:958! Oops: Exception in kernel mode, sig: 5 [#1] LE SMP NR_CPUS=2048 NUMA pSeries Modules linked in: nfsv3 nfs_acl nfs tcp_diag udp_diag inet_diag lockd unix_diag af_packet_diag netlink_diag grace fscache sunrpc xts vmx_crypto pseries_rng sg binfmt_misc ip_tables xfs libcrc32c sd_mod ibmvscsi ibmveth scsi_transport_srp dm_mirror dm_region_hash dm_log dm_mod CPU: 11 PID: 3067 Comm: drmgr Not tainted 4.17.0+ #179 ... NIP mod_timer+0x4c/0x400 LR reset_topology_timer+0x40/0x60 Call Trace: 0xc0000003f9407830 (unreliable) reset_topology_timer+0x40/0x60 dt_update_callback+0x100/0x120 notifier_call_chain+0x90/0x100 __blocking_notifier_call_chain+0x60/0x90 of_property_notify+0x90/0xd0 of_update_property+0x104/0x150 update_dt_property+0xdc/0x1f0 pseries_devicetree_update+0x2d0/0x510 post_mobility_fixup+0x7c/0xf0 migration_store+0xa4/0xc0 kobj_attr_store+0x30/0x60 sysfs_kf_write+0x64/0xa0 kernfs_fop_write+0x16c/0x240 __vfs_write+0x40/0x200 vfs_write+0xc8/0x240 ksys_write+0x5c/0x100 system_call+0x58/0x6c Fixes: 5d88aa85c00b ("powerpc/pseries: Update CPU maps when device tree is updated") Cc: stable@vger.kernel.org # v3.10+ Signed-off-by: Michael Bringmann Signed-off-by: Michael Ellerman --- arch/powerpc/mm/numa.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 35ac5422903a0..b5a71baedbc25 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1452,7 +1452,8 @@ static struct timer_list topology_timer; static void reset_topology_timer(void) { - mod_timer(&topology_timer, jiffies + topology_timer_secs * HZ); + if (vphn_enabled) + mod_timer(&topology_timer, jiffies + topology_timer_secs * HZ); } #ifdef CONFIG_SMP From cf13435b730a502e814c63c84d93db131e563f5f Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Mon, 24 Sep 2018 17:27:04 +1000 Subject: [PATCH 07/14] powerpc/tm: Fix userspace r13 corruption When we treclaim we store the userspace checkpointed r13 to a scratch SPR and then later save the scratch SPR to the user thread struct. Unfortunately, this doesn't work as accessing the user thread struct can take an SLB fault and the SLB fault handler will write the same scratch SPRG that now contains the userspace r13. To fix this, we store r13 to the kernel stack (which can't fault) before we access the user thread struct. Found by running P8 guest + powervm + disable_1tb_segments + TM. Seen as a random userspace segfault with r13 looking like a kernel address. Signed-off-by: Michael Neuling Reviewed-by: Breno Leitao Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/tm.S | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/tm.S b/arch/powerpc/kernel/tm.S index 6bffbc5affe76..183e8d75936f1 100644 --- a/arch/powerpc/kernel/tm.S +++ b/arch/powerpc/kernel/tm.S @@ -176,13 +176,20 @@ _GLOBAL(tm_reclaim) std r1, PACATMSCRATCH(r13) ld r1, PACAR1(r13) - /* Store the PPR in r11 and reset to decent value */ std r11, GPR11(r1) /* Temporary stash */ + /* + * Store r13 away so we can free up the scratch SPR for the SLB fault + * handler (needed once we start accessing the thread_struct). + */ + GET_SCRATCH0(r11) + std r11, GPR13(r1) + /* Reset MSR RI so we can take SLB faults again */ li r11, MSR_RI mtmsrd r11, 1 + /* Store the PPR in r11 and reset to decent value */ mfspr r11, SPRN_PPR HMT_MEDIUM @@ -211,7 +218,7 @@ _GLOBAL(tm_reclaim) ld r4, GPR7(r1) /* user r7 */ ld r5, GPR11(r1) /* user r11 */ ld r6, GPR12(r1) /* user r12 */ - GET_SCRATCH0(8) /* user r13 */ + ld r8, GPR13(r1) /* user r13 */ std r3, GPR1(r7) std r4, GPR7(r7) std r5, GPR11(r7) From 96dc89d526ef77604376f06220e3d2931a0bfd58 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Tue, 25 Sep 2018 19:36:47 +1000 Subject: [PATCH 08/14] powerpc/tm: Avoid possible userspace r1 corruption on reclaim Current we store the userspace r1 to PACATMSCRATCH before finally saving it to the thread struct. In theory an exception could be taken here (like a machine check or SLB miss) that could write PACATMSCRATCH and hence corrupt the userspace r1. The SLB fault currently doesn't touch PACATMSCRATCH, but others do. We've never actually seen this happen but it's theoretically possible. Either way, the code is fragile as it is. This patch saves r1 to the kernel stack (which can't fault) before we turn MSR[RI] back on. PACATMSCRATCH is still used but only with MSR[RI] off. We then copy r1 from the kernel stack to the thread struct once we have MSR[RI] back on. Suggested-by: Breno Leitao Signed-off-by: Michael Neuling Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/tm.S | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/tm.S b/arch/powerpc/kernel/tm.S index 183e8d75936f1..7716374786bd9 100644 --- a/arch/powerpc/kernel/tm.S +++ b/arch/powerpc/kernel/tm.S @@ -178,6 +178,13 @@ _GLOBAL(tm_reclaim) std r11, GPR11(r1) /* Temporary stash */ + /* + * Move the saved user r1 to the kernel stack in case PACATMSCRATCH is + * clobbered by an exception once we turn on MSR_RI below. + */ + ld r11, PACATMSCRATCH(r13) + std r11, GPR1(r1) + /* * Store r13 away so we can free up the scratch SPR for the SLB fault * handler (needed once we start accessing the thread_struct). @@ -214,7 +221,7 @@ _GLOBAL(tm_reclaim) SAVE_GPR(8, r7) /* user r8 */ SAVE_GPR(9, r7) /* user r9 */ SAVE_GPR(10, r7) /* user r10 */ - ld r3, PACATMSCRATCH(r13) /* user r1 */ + ld r3, GPR1(r1) /* user r1 */ ld r4, GPR7(r1) /* user r7 */ ld r5, GPR11(r1) /* user r11 */ ld r6, GPR12(r1) /* user r12 */ From 2483ef056f6e42f61cd266452e2841165dfe1b5c Mon Sep 17 00:00:00 2001 From: Srikar Dronamraju Date: Tue, 25 Sep 2018 17:55:15 +0530 Subject: [PATCH 09/14] powerpc/numa: Use associativity if VPHN hcall is successful Currently associativity is used to lookup node-id even if the preceding VPHN hcall failed. However this can cause CPU to be made part of the wrong node, (most likely to be node 0). This is because VPHN is not enabled on KVM guests. With 2ea6263 ("powerpc/topology: Get topology for shared processors at boot"), associativity is used to set to the wrong node. Hence KVM guest topology is broken. For example : A 4 node KVM guest before would have reported. [root@localhost ~]# numactl -H available: 4 nodes (0-3) node 0 cpus: 0 1 2 3 node 0 size: 1746 MB node 0 free: 1604 MB node 1 cpus: 4 5 6 7 node 1 size: 2044 MB node 1 free: 1765 MB node 2 cpus: 8 9 10 11 node 2 size: 2044 MB node 2 free: 1837 MB node 3 cpus: 12 13 14 15 node 3 size: 2044 MB node 3 free: 1903 MB node distances: node 0 1 2 3 0: 10 40 40 40 1: 40 10 40 40 2: 40 40 10 40 3: 40 40 40 10 Would now report: [root@localhost ~]# numactl -H available: 4 nodes (0-3) node 0 cpus: 0 2 3 4 5 6 7 8 9 10 11 12 13 14 15 node 0 size: 1746 MB node 0 free: 1244 MB node 1 cpus: node 1 size: 2044 MB node 1 free: 2032 MB node 2 cpus: 1 node 2 size: 2044 MB node 2 free: 2028 MB node 3 cpus: node 3 size: 2044 MB node 3 free: 2032 MB node distances: node 0 1 2 3 0: 10 40 40 40 1: 40 10 40 40 2: 40 40 10 40 3: 40 40 40 10 Fix this by skipping associativity lookup if the VPHN hcall failed. Fixes: 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot") Signed-off-by: Srikar Dronamraju Signed-off-by: Michael Ellerman --- arch/powerpc/mm/numa.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index b5a71baedbc25..59d07bd5374a9 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1204,7 +1204,9 @@ int find_and_online_cpu_nid(int cpu) int new_nid; /* Use associativity from first thread for all siblings */ - vphn_get_associativity(cpu, associativity); + if (vphn_get_associativity(cpu, associativity)) + return cpu_to_node(cpu); + new_nid = associativity_to_nid(associativity); if (new_nid < 0 || !node_possible(new_nid)) new_nid = first_online_node; From 7e0cf1c983b5b24426d130fd949a055d520acc9a Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Fri, 28 Sep 2018 14:53:18 +1000 Subject: [PATCH 10/14] selftests/powerpc: Fix Makefiles for headers_install change Commit b2d35fa5fc80 ("selftests: add headers_install to lib.mk") introduced a requirement that Makefiles more than one level below the selftests directory need to define top_srcdir, but it didn't update any of the powerpc Makefiles. This broke building all the powerpc selftests with eg: make[1]: Entering directory '/src/linux/tools/testing/selftests/powerpc' BUILD_TARGET=/src/linux/tools/testing/selftests/powerpc/alignment; mkdir -p $BUILD_TARGET; make OUTPUT=$BUILD_TARGET -k -C alignment all make[2]: Entering directory '/src/linux/tools/testing/selftests/powerpc/alignment' ../../lib.mk:20: ../../../../scripts/subarch.include: No such file or directory make[2]: *** No rule to make target '../../../../scripts/subarch.include'. make[2]: Failed to remake makefile '../../../../scripts/subarch.include'. Makefile:38: recipe for target 'alignment' failed Fix it by setting top_srcdir in the affected Makefiles. Fixes: b2d35fa5fc80 ("selftests: add headers_install to lib.mk") Signed-off-by: Michael Ellerman --- tools/testing/selftests/powerpc/alignment/Makefile | 1 + tools/testing/selftests/powerpc/benchmarks/Makefile | 1 + tools/testing/selftests/powerpc/cache_shape/Makefile | 1 + tools/testing/selftests/powerpc/copyloops/Makefile | 1 + tools/testing/selftests/powerpc/dscr/Makefile | 1 + tools/testing/selftests/powerpc/math/Makefile | 1 + tools/testing/selftests/powerpc/mm/Makefile | 1 + tools/testing/selftests/powerpc/pmu/Makefile | 1 + tools/testing/selftests/powerpc/pmu/ebb/Makefile | 1 + tools/testing/selftests/powerpc/primitives/Makefile | 1 + tools/testing/selftests/powerpc/ptrace/Makefile | 1 + tools/testing/selftests/powerpc/signal/Makefile | 1 + tools/testing/selftests/powerpc/stringloops/Makefile | 1 + tools/testing/selftests/powerpc/switch_endian/Makefile | 1 + tools/testing/selftests/powerpc/syscalls/Makefile | 1 + tools/testing/selftests/powerpc/tm/Makefile | 1 + tools/testing/selftests/powerpc/vphn/Makefile | 1 + 17 files changed, 17 insertions(+) diff --git a/tools/testing/selftests/powerpc/alignment/Makefile b/tools/testing/selftests/powerpc/alignment/Makefile index 93baacab7693c..d056486f49de5 100644 --- a/tools/testing/selftests/powerpc/alignment/Makefile +++ b/tools/testing/selftests/powerpc/alignment/Makefile @@ -1,5 +1,6 @@ TEST_GEN_PROGS := copy_first_unaligned alignment_handler +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): ../harness.c ../utils.c diff --git a/tools/testing/selftests/powerpc/benchmarks/Makefile b/tools/testing/selftests/powerpc/benchmarks/Makefile index b4d7432a0ecd1..d40300a65b42f 100644 --- a/tools/testing/selftests/powerpc/benchmarks/Makefile +++ b/tools/testing/selftests/powerpc/benchmarks/Makefile @@ -4,6 +4,7 @@ TEST_GEN_FILES := exec_target CFLAGS += -O2 +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): ../harness.c diff --git a/tools/testing/selftests/powerpc/cache_shape/Makefile b/tools/testing/selftests/powerpc/cache_shape/Makefile index 1be547434a49c..ede4d3dae7505 100644 --- a/tools/testing/selftests/powerpc/cache_shape/Makefile +++ b/tools/testing/selftests/powerpc/cache_shape/Makefile @@ -5,6 +5,7 @@ all: $(TEST_PROGS) $(TEST_PROGS): ../harness.c ../utils.c +top_srcdir = ../../../../.. include ../../lib.mk clean: diff --git a/tools/testing/selftests/powerpc/copyloops/Makefile b/tools/testing/selftests/powerpc/copyloops/Makefile index 1cf89a34d97ca..44574f3818b3d 100644 --- a/tools/testing/selftests/powerpc/copyloops/Makefile +++ b/tools/testing/selftests/powerpc/copyloops/Makefile @@ -17,6 +17,7 @@ TEST_GEN_PROGS := copyuser_64_t0 copyuser_64_t1 copyuser_64_t2 \ EXTRA_SOURCES := validate.c ../harness.c stubs.S +top_srcdir = ../../../../.. include ../../lib.mk $(OUTPUT)/copyuser_64_t%: copyuser_64.S $(EXTRA_SOURCES) diff --git a/tools/testing/selftests/powerpc/dscr/Makefile b/tools/testing/selftests/powerpc/dscr/Makefile index 55d7db7a616bc..5df476364b4d4 100644 --- a/tools/testing/selftests/powerpc/dscr/Makefile +++ b/tools/testing/selftests/powerpc/dscr/Makefile @@ -3,6 +3,7 @@ TEST_GEN_PROGS := dscr_default_test dscr_explicit_test dscr_user_test \ dscr_inherit_test dscr_inherit_exec_test dscr_sysfs_test \ dscr_sysfs_thread_test +top_srcdir = ../../../../.. include ../../lib.mk $(OUTPUT)/dscr_default_test: LDLIBS += -lpthread diff --git a/tools/testing/selftests/powerpc/math/Makefile b/tools/testing/selftests/powerpc/math/Makefile index 0dd3a01fdab92..11a10d7a2bbd9 100644 --- a/tools/testing/selftests/powerpc/math/Makefile +++ b/tools/testing/selftests/powerpc/math/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 TEST_GEN_PROGS := fpu_syscall fpu_preempt fpu_signal vmx_syscall vmx_preempt vmx_signal vsx_preempt +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): ../harness.c diff --git a/tools/testing/selftests/powerpc/mm/Makefile b/tools/testing/selftests/powerpc/mm/Makefile index 8ebbe96d80a84..33ced6e0ad25e 100644 --- a/tools/testing/selftests/powerpc/mm/Makefile +++ b/tools/testing/selftests/powerpc/mm/Makefile @@ -5,6 +5,7 @@ noarg: TEST_GEN_PROGS := hugetlb_vs_thp_test subpage_prot prot_sao segv_errors TEST_GEN_FILES := tempfile +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): ../harness.c diff --git a/tools/testing/selftests/powerpc/pmu/Makefile b/tools/testing/selftests/powerpc/pmu/Makefile index 6e1629bf5b09d..19046db995fee 100644 --- a/tools/testing/selftests/powerpc/pmu/Makefile +++ b/tools/testing/selftests/powerpc/pmu/Makefile @@ -5,6 +5,7 @@ noarg: TEST_GEN_PROGS := count_instructions l3_bank_test per_event_excludes EXTRA_SOURCES := ../harness.c event.c lib.c ../utils.c +top_srcdir = ../../../../.. include ../../lib.mk all: $(TEST_GEN_PROGS) ebb diff --git a/tools/testing/selftests/powerpc/pmu/ebb/Makefile b/tools/testing/selftests/powerpc/pmu/ebb/Makefile index c4e64bc2e2650..bd5dfa509272a 100644 --- a/tools/testing/selftests/powerpc/pmu/ebb/Makefile +++ b/tools/testing/selftests/powerpc/pmu/ebb/Makefile @@ -17,6 +17,7 @@ TEST_GEN_PROGS := reg_access_test event_attributes_test cycles_test \ lost_exception_test no_handler_test \ cycles_with_mmcr2_test +top_srcdir = ../../../../../.. include ../../../lib.mk $(TEST_GEN_PROGS): ../../harness.c ../../utils.c ../event.c ../lib.c \ diff --git a/tools/testing/selftests/powerpc/primitives/Makefile b/tools/testing/selftests/powerpc/primitives/Makefile index 175366db7be8b..ea2b7bd09e369 100644 --- a/tools/testing/selftests/powerpc/primitives/Makefile +++ b/tools/testing/selftests/powerpc/primitives/Makefile @@ -2,6 +2,7 @@ CFLAGS += -I$(CURDIR) TEST_GEN_PROGS := load_unaligned_zeropad +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): ../harness.c diff --git a/tools/testing/selftests/powerpc/ptrace/Makefile b/tools/testing/selftests/powerpc/ptrace/Makefile index 28f5b781a553f..923d531265f8c 100644 --- a/tools/testing/selftests/powerpc/ptrace/Makefile +++ b/tools/testing/selftests/powerpc/ptrace/Makefile @@ -4,6 +4,7 @@ TEST_PROGS := ptrace-gpr ptrace-tm-gpr ptrace-tm-spd-gpr \ ptrace-tm-spd-vsx ptrace-tm-spr ptrace-hwbreak ptrace-pkey core-pkey \ perf-hwbreak +top_srcdir = ../../../../.. include ../../lib.mk all: $(TEST_PROGS) diff --git a/tools/testing/selftests/powerpc/signal/Makefile b/tools/testing/selftests/powerpc/signal/Makefile index a7cbd5082e271..1fca25c6ace06 100644 --- a/tools/testing/selftests/powerpc/signal/Makefile +++ b/tools/testing/selftests/powerpc/signal/Makefile @@ -8,6 +8,7 @@ $(TEST_PROGS): ../harness.c ../utils.c signal.S CFLAGS += -maltivec signal_tm: CFLAGS += -mhtm +top_srcdir = ../../../../.. include ../../lib.mk clean: diff --git a/tools/testing/selftests/powerpc/stringloops/Makefile b/tools/testing/selftests/powerpc/stringloops/Makefile index 10b35c87a4f4e..7fc0623d85c31 100644 --- a/tools/testing/selftests/powerpc/stringloops/Makefile +++ b/tools/testing/selftests/powerpc/stringloops/Makefile @@ -29,6 +29,7 @@ endif ASFLAGS = $(CFLAGS) +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): $(EXTRA_SOURCES) diff --git a/tools/testing/selftests/powerpc/switch_endian/Makefile b/tools/testing/selftests/powerpc/switch_endian/Makefile index 30b8ff8fb82e7..fcd2dcb8972ba 100644 --- a/tools/testing/selftests/powerpc/switch_endian/Makefile +++ b/tools/testing/selftests/powerpc/switch_endian/Makefile @@ -5,6 +5,7 @@ ASFLAGS += -O2 -Wall -g -nostdlib -m64 EXTRA_CLEAN = $(OUTPUT)/*.o $(OUTPUT)/check-reversed.S +top_srcdir = ../../../../.. include ../../lib.mk $(OUTPUT)/switch_endian_test: $(OUTPUT)/check-reversed.S diff --git a/tools/testing/selftests/powerpc/syscalls/Makefile b/tools/testing/selftests/powerpc/syscalls/Makefile index da22ca7c38c18..161b8846336fd 100644 --- a/tools/testing/selftests/powerpc/syscalls/Makefile +++ b/tools/testing/selftests/powerpc/syscalls/Makefile @@ -2,6 +2,7 @@ TEST_GEN_PROGS := ipc_unmuxed CFLAGS += -I../../../../../usr/include +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): ../harness.c diff --git a/tools/testing/selftests/powerpc/tm/Makefile b/tools/testing/selftests/powerpc/tm/Makefile index c0e45d2dde25d..9fc2cf6fbc92c 100644 --- a/tools/testing/selftests/powerpc/tm/Makefile +++ b/tools/testing/selftests/powerpc/tm/Makefile @@ -6,6 +6,7 @@ TEST_GEN_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-signal-stack tm-vmxcopy tm-fork tm-tar tm-tmspr tm-vmx-unavail tm-unavailable tm-trap \ $(SIGNAL_CONTEXT_CHK_TESTS) tm-sigreturn +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): ../harness.c ../utils.c diff --git a/tools/testing/selftests/powerpc/vphn/Makefile b/tools/testing/selftests/powerpc/vphn/Makefile index f8ced26748f84..fb82068c9fda2 100644 --- a/tools/testing/selftests/powerpc/vphn/Makefile +++ b/tools/testing/selftests/powerpc/vphn/Makefile @@ -2,6 +2,7 @@ TEST_GEN_PROGS := test-vphn CFLAGS += -m64 +top_srcdir = ../../../../.. include ../../lib.mk $(TEST_GEN_PROGS): ../harness.c From 242cdad873a75652f97c35aad61270581e0f3a2e Mon Sep 17 00:00:00 2001 From: Joel Stanley Date: Fri, 21 Sep 2018 12:24:31 +0930 Subject: [PATCH 11/14] lib/xz: Put CRC32_POLY_LE in xz_private.h This fixes a regression introduced by faa16bc404d72a5 ("lib: Use existing define with polynomial"). The cleanup added a dependency on include/linux, which broke the PowerPC boot wrapper/decompresser when KERNEL_XZ is enabled: BOOTCC arch/powerpc/boot/decompress.o In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:233, from arch/powerpc/boot/decompress.c:42: arch/powerpc/boot/../../../lib/xz/xz_crc32.c:18:10: fatal error: linux/crc32poly.h: No such file or directory #include ^~~~~~~~~~~~~~~~~~~ The powerpc decompresser is a hairy corner of the kernel. Even while building a 64-bit kernel it needs to build a 32-bit binary and therefore avoid including files from include/linux. This allows users of the xz library to avoid including headers from 'include/linux/' while still achieving the cleanup of the magic number. Fixes: faa16bc404d72a5 ("lib: Use existing define with polynomial") Reported-by: Meelis Roos Reported-by: kbuild test robot Suggested-by: Christophe LEROY Signed-off-by: Joel Stanley Tested-by: Meelis Roos Signed-off-by: Michael Ellerman --- lib/xz/xz_crc32.c | 1 - lib/xz/xz_private.h | 4 ++++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/lib/xz/xz_crc32.c b/lib/xz/xz_crc32.c index 25a5d87e2e4c6..912aae5fa09e1 100644 --- a/lib/xz/xz_crc32.c +++ b/lib/xz/xz_crc32.c @@ -15,7 +15,6 @@ * but they are bigger and use more memory for the lookup table. */ -#include #include "xz_private.h" /* diff --git a/lib/xz/xz_private.h b/lib/xz/xz_private.h index 482b90f363fe3..09360ebb510ef 100644 --- a/lib/xz/xz_private.h +++ b/lib/xz/xz_private.h @@ -102,6 +102,10 @@ # endif #endif +#ifndef CRC32_POLY_LE +#define CRC32_POLY_LE 0xedb88320 +#endif + /* * Allocate memory for LZMA2 decoder. xz_dec_lzma2_reset() must be used * before calling xz_dec_lzma2_run(). From b45ba4a51cde29b2939365ef0c07ad34c8321789 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 1 Oct 2018 12:21:10 +0000 Subject: [PATCH 12/14] powerpc/lib: fix book3s/32 boot failure due to code patching Commit 51c3c62b58b3 ("powerpc: Avoid code patching freed init sections") accesses 'init_mem_is_free' flag too early, before the kernel is relocated. This provokes early boot failure (before the console is active). As it is not necessary to do this verification that early, this patch moves the test into patch_instruction() instead of __patch_instruction(). This modification also has the advantage of avoiding unnecessary remappings. Fixes: 51c3c62b58b3 ("powerpc: Avoid code patching freed init sections") Cc: stable@vger.kernel.org # 4.13+ Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/lib/code-patching.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 6ae2777c220d4..5ffee298745fe 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -28,12 +28,6 @@ static int __patch_instruction(unsigned int *exec_addr, unsigned int instr, { int err; - /* Make sure we aren't patching a freed init section */ - if (init_mem_is_free && init_section_contains(exec_addr, 4)) { - pr_debug("Skipping init section patching addr: 0x%px\n", exec_addr); - return 0; - } - __put_user_size(instr, patch_addr, 4, err); if (err) return err; @@ -148,7 +142,7 @@ static inline int unmap_patch_area(unsigned long addr) return 0; } -int patch_instruction(unsigned int *addr, unsigned int instr) +static int do_patch_instruction(unsigned int *addr, unsigned int instr) { int err; unsigned int *patch_addr = NULL; @@ -188,12 +182,22 @@ int patch_instruction(unsigned int *addr, unsigned int instr) } #else /* !CONFIG_STRICT_KERNEL_RWX */ -int patch_instruction(unsigned int *addr, unsigned int instr) +static int do_patch_instruction(unsigned int *addr, unsigned int instr) { return raw_patch_instruction(addr, instr); } #endif /* CONFIG_STRICT_KERNEL_RWX */ + +int patch_instruction(unsigned int *addr, unsigned int instr) +{ + /* Make sure we aren't patching a freed init section */ + if (init_mem_is_free && init_section_contains(addr, 4)) { + pr_debug("Skipping init section patching addr: 0x%px\n", addr); + return 0; + } + return do_patch_instruction(addr, instr); +} NOKPROBE_SYMBOL(patch_instruction); int patch_branch(unsigned int *addr, unsigned long target, int flags) From a932ed3b718147c6537da290b7a91e990fdedb43 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Fri, 5 Oct 2018 16:43:55 +1000 Subject: [PATCH 13/14] powerpc: Don't print kernel instructions in show_user_instructions() Recently we implemented show_user_instructions() which dumps the code around the NIP when a user space process dies with an unhandled signal. This was modelled on the x86 code, and we even went so far as to implement the exact same bug, namely that if the user process crashed with its NIP pointing into the kernel we will dump kernel text to dmesg. eg: bad-bctr[2996]: segfault (11) at c000000000010000 nip c000000000010000 lr 12d0b0894 code 1 bad-bctr[2996]: code: fbe10068 7cbe2b78 7c7f1b78 fb610048 38a10028 38810020 fb810050 7f8802a6 bad-bctr[2996]: code: 3860001c f8010080 48242371 60000000 <7c7b1b79> 4082002c e8010080 eb610048 This was discovered on x86 by Jann Horn and fixed in commit 342db04ae712 ("x86/dumpstack: Don't dump kernel memory based on usermode RIP"). Fix it by checking the adjusted NIP value (pc) and number of instructions against USER_DS, and bail if we fail the check, eg: bad-bctr[2969]: segfault (11) at c000000000010000 nip c000000000010000 lr 107930894 code 1 bad-bctr[2969]: Bad NIP, not dumping instructions. Fixes: 88b0fe175735 ("powerpc: Add show_user_instructions()") Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/process.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 913c5725cdb2a..bb6ac471a784e 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1306,6 +1306,16 @@ void show_user_instructions(struct pt_regs *regs) pc = regs->nip - (instructions_to_print * 3 / 4 * sizeof(int)); + /* + * Make sure the NIP points at userspace, not kernel text/data or + * elsewhere. + */ + if (!__access_ok(pc, instructions_to_print * sizeof(int), USER_DS)) { + pr_info("%s[%d]: Bad NIP, not dumping instructions.\n", + current->comm, current->pid); + return; + } + pr_info("%s[%d]: code: ", current->comm, current->pid); for (i = 0; i < instructions_to_print; i++) { From ac1788cc7da4ce54edcfd2e499afdb0a23d5c41d Mon Sep 17 00:00:00 2001 From: Srikar Dronamraju Date: Fri, 28 Sep 2018 09:17:32 +0530 Subject: [PATCH 14/14] powerpc/numa: Skip onlining a offline node in kdump path With commit 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot"), kdump kernel on shared LPAR may crash. The necessary conditions are - Shared LPAR with at least 2 nodes having memory and CPUs. - Memory requirement for kdump kernel must be met by the first N-1 nodes where there are at least N nodes with memory and CPUs. Example numactl of such a machine. $ numactl -H available: 5 nodes (0,2,5-7) node 0 cpus: node 0 size: 0 MB node 0 free: 0 MB node 2 cpus: node 2 size: 255 MB node 2 free: 189 MB node 5 cpus: 24 25 26 27 28 29 30 31 node 5 size: 4095 MB node 5 free: 4024 MB node 6 cpus: 0 1 2 3 4 5 6 7 16 17 18 19 20 21 22 23 node 6 size: 6353 MB node 6 free: 5998 MB node 7 cpus: 8 9 10 11 12 13 14 15 32 33 34 35 36 37 38 39 node 7 size: 7640 MB node 7 free: 7164 MB node distances: node 0 2 5 6 7 0: 10 40 40 40 40 2: 40 10 40 40 40 5: 40 40 10 40 40 6: 40 40 40 10 20 7: 40 40 40 20 10 Steps to reproduce. 1. Load / start kdump service. 2. Trigger a kdump (for example : echo c > /proc/sysrq-trigger) When booting a kdump kernel with 2048M: kexec: Starting switchover sequence. I'm in purgatory Using 1TB segments hash-mmu: Initializing hash mmu with SLB Linux version 4.19.0-rc5-master+ (srikar@linux-xxu6) (gcc version 4.8.5 (SUSE Linux)) #1 SMP Thu Sep 27 19:45:00 IST 2018 Found initrd at 0xc000000009e70000:0xc00000000ae554b4 Using pSeries machine description ----------------------------------------------------- ppc64_pft_size = 0x1e phys_mem_size = 0x88000000 dcache_bsize = 0x80 icache_bsize = 0x80 cpu_features = 0x000000ff8f5d91a7 possible = 0x0000fbffcf5fb1a7 always = 0x0000006f8b5c91a1 cpu_user_features = 0xdc0065c2 0xef000000 mmu_features = 0x7c006001 firmware_features = 0x00000007c45bfc57 htab_hash_mask = 0x7fffff physical_start = 0x8000000 ----------------------------------------------------- numa: NODE_DATA [mem 0x87d5e300-0x87d67fff] numa: NODE_DATA(0) on node 6 numa: NODE_DATA [mem 0x87d54600-0x87d5e2ff] Top of RAM: 0x88000000, Total RAM: 0x88000000 Memory hole size: 0MB Zone ranges: DMA [mem 0x0000000000000000-0x0000000087ffffff] DMA32 empty Normal empty Movable zone start for each node Early memory node ranges node 6: [mem 0x0000000000000000-0x0000000087ffffff] Could not find start_pfn for node 0 Initmem setup node 0 [mem 0x0000000000000000-0x0000000000000000] On node 0 totalpages: 0 Initmem setup node 6 [mem 0x0000000000000000-0x0000000087ffffff] On node 6 totalpages: 34816 Unable to handle kernel paging request for data at address 0x00000060 Faulting instruction address: 0xc000000008703a54 Oops: Kernel access of bad area, sig: 11 [#1] LE SMP NR_CPUS=2048 NUMA pSeries Modules linked in: CPU: 11 PID: 1 Comm: swapper/11 Not tainted 4.19.0-rc5-master+ #1 NIP: c000000008703a54 LR: c000000008703a38 CTR: 0000000000000000 REGS: c00000000b673440 TRAP: 0380 Not tainted (4.19.0-rc5-master+) MSR: 8000000002009033 CR: 24022022 XER: 20000002 CFAR: c0000000086fc238 IRQMASK: 0 GPR00: c000000008703a38 c00000000b6736c0 c000000009281900 0000000000000000 GPR04: 0000000000000000 0000000000000000 fffffffffffff001 c00000000b660080 GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000220 GPR12: 0000000000002200 c000000009e51400 0000000000000000 0000000000000008 GPR16: 0000000000000000 c000000008c152e8 c000000008c152a8 0000000000000000 GPR20: c000000009422fd8 c000000009412fd8 c000000009426040 0000000000000008 GPR24: 0000000000000000 0000000000000000 c000000009168bc8 c000000009168c78 GPR28: c00000000b126410 0000000000000000 c00000000916a0b8 c00000000b126400 NIP [c000000008703a54] bus_add_device+0x84/0x1e0 LR [c000000008703a38] bus_add_device+0x68/0x1e0 Call Trace: [c00000000b6736c0] [c000000008703a38] bus_add_device+0x68/0x1e0 (unreliable) [c00000000b673740] [c000000008700194] device_add+0x454/0x7c0 [c00000000b673800] [c00000000872e660] __register_one_node+0xb0/0x240 [c00000000b673860] [c00000000839a6bc] __try_online_node+0x12c/0x180 [c00000000b673900] [c00000000839b978] try_online_node+0x58/0x90 [c00000000b673930] [c0000000080846d8] find_and_online_cpu_nid+0x158/0x190 [c00000000b673a10] [c0000000080848a0] numa_update_cpu_topology+0x190/0x580 [c00000000b673c00] [c000000008d3f2e4] smp_cpus_done+0x94/0x108 [c00000000b673c70] [c000000008d5c00c] smp_init+0x174/0x19c [c00000000b673d00] [c000000008d346b8] kernel_init_freeable+0x1e0/0x450 [c00000000b673dc0] [c0000000080102e8] kernel_init+0x28/0x160 [c00000000b673e30] [c00000000800b65c] ret_from_kernel_thread+0x5c/0x80 Instruction dump: 60000000 60000000 e89e0020 7fe3fb78 4bff87d5 60000000 7c7d1b79 4082008c e8bf0050 e93e0098 3b9f0010 2fa50000 38630018 419e0114 7f84e378 ---[ end trace 593577668c2daa65 ]--- However a regular kernel with 4096M (2048 gets reserved for crash kernel) boots properly. Unlike regular kernels, which mark all available nodes as online, kdump kernel only marks just enough nodes as online and marks the rest as offline at boot. However kdump kernel boots with all available CPUs. With Commit 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot"), all CPUs are onlined on their respective nodes at boot time. try_online_node() tries to online the offline nodes but fails as all needed subsystems are not yet initialized. As part of fix, detect and skip early onlining of a offline node. Fixes: 2ea626306810 ("powerpc/topology: Get topology for shared processors at boot") Reported-by: Pavithra Prakash Signed-off-by: Srikar Dronamraju Tested-by: Hari Bathini Signed-off-by: Michael Ellerman --- arch/powerpc/mm/numa.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 59d07bd5374a9..055b211b71266 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1217,9 +1217,10 @@ int find_and_online_cpu_nid(int cpu) * Need to ensure that NODE_DATA is initialized for a node from * available memory (see memblock_alloc_try_nid). If unable to * init the node, then default to nearest node that has memory - * installed. + * installed. Skip onlining a node if the subsystems are not + * yet initialized. */ - if (try_online_node(new_nid)) + if (!topology_inited || try_online_node(new_nid)) new_nid = first_online_node; #else /*