From 2a58222f8220089c7b602cf5fae557e0bc0bc303 Mon Sep 17 00:00:00 2001 From: Wei Yang Date: Wed, 17 Sep 2014 10:48:26 +0800 Subject: [PATCH] powerpc/eeh: Fix kernel crash when passing through VF When doing vfio passthrough a VF, the kernel will crash with following message: [ 442.656459] Unable to handle kernel paging request for data at address 0x00000060 [ 442.656593] Faulting instruction address: 0xc000000000038b88 [ 442.656706] Oops: Kernel access of bad area, sig: 11 [#1] [ 442.656798] SMP NR_CPUS=1024 NUMA PowerNV [ 442.656890] Modules linked in: vfio_pci mlx4_core nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT xt_conntrack bnep bluetooth rfkill ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw tg3 nfsd be2net nfs_acl ses lockd ptp enclosure pps_core kvm_hv kvm_pr shpchp binfmt_misc kvm sunrpc uinput lpfc scsi_transport_fc ipr scsi_tgt [last unloaded: mlx4_core] [ 442.658152] CPU: 40 PID: 14948 Comm: qemu-system-ppc Not tainted 3.10.42yw-pkvm+ #37 [ 442.658219] task: c000000f7e2a9a00 ti: c000000f6dc3c000 task.ti: c000000f6dc3c000 [ 442.658287] NIP: c000000000038b88 LR: c0000000004435a8 CTR: c000000000455bc0 [ 442.658352] REGS: c000000f6dc3f580 TRAP: 0300 Not tainted (3.10.42yw-pkvm+) [ 442.658419] MSR: 9000000000009032 CR: 28004882 XER: 20000000 [ 442.658577] CFAR: c00000000000908c DAR: 0000000000000060 DSISR: 40000000 SOFTE: 1 GPR00: c0000000004435a8 c000000f6dc3f800 c0000000012b1c10 c00000000da24000 GPR04: 0000000000000003 0000000000001004 00000000000015b3 000000000000ffff GPR08: c00000000127f5d8 0000000000000000 000000000000ffff 0000000000000000 GPR12: c000000000068078 c00000000fdd6800 000001003c320c80 000001003c3607f0 GPR16: 0000000000000001 00000000105480c8 000000001055aaa8 000001003c31ab18 GPR20: 000001003c10fb40 000001003c360ae8 000000001063bcf0 000000001063bdb0 GPR24: 000001003c15ed70 0000000010548f40 c000001fe5514c88 c000001fe5514cb0 GPR28: c00000000da24000 0000000000000000 c00000000da24000 0000000000000003 [ 442.659471] NIP [c000000000038b88] .pcibios_set_pcie_reset_state+0x28/0x130 [ 442.659530] LR [c0000000004435a8] .pci_set_pcie_reset_state+0x28/0x40 [ 442.659585] Call Trace: [ 442.659610] [c000000f6dc3f800] [00000000000719e0] 0x719e0 (unreliable) [ 442.659677] [c000000f6dc3f880] [c0000000004435a8] .pci_set_pcie_reset_state+0x28/0x40 [ 442.659757] [c000000f6dc3f900] [c000000000455bf8] .reset_fundamental+0x38/0x80 [ 442.659835] [c000000f6dc3f980] [c0000000004562a8] .pci_dev_specific_reset+0xa8/0xf0 [ 442.659913] [c000000f6dc3fa00] [c0000000004448c4] .__pci_dev_reset+0x44/0x430 [ 442.659980] [c000000f6dc3fab0] [c000000000444d5c] .pci_reset_function+0x7c/0xc0 [ 442.660059] [c000000f6dc3fb30] [d00000001c141ab8] .vfio_pci_open+0xe8/0x2b0 [vfio_pci] [ 442.660139] [c000000f6dc3fbd0] [c000000000586c30] .vfio_group_fops_unl_ioctl+0x3a0/0x630 [ 442.660219] [c000000f6dc3fc90] [c000000000255fbc] .do_vfs_ioctl+0x4ec/0x7c0 [ 442.660286] [c000000f6dc3fd80] [c000000000256364] .SyS_ioctl+0xd4/0xf0 [ 442.660354] [c000000f6dc3fe30] [c000000000009e54] syscall_exit+0x0/0x98 [ 442.660420] Instruction dump: [ 442.660454] 4bfffce9 4bfffee4 7c0802a6 fbc1fff0 fbe1fff8 f8010010 f821ff81 7c7e1b78 [ 442.660566] 7c9f2378 60000000 60000000 e93e02c8 2fa30000 41de00c4 2b9f0002 [ 442.660679] ---[ end trace a64ac9546bcf0328 ]--- [ 442.660724] The reason is current VF is not EEH enabled. This patch introduces a macro to convert eeh_dev to eeh_pe. By doing so, it will prevent converting with NULL pointer. Signed-off-by: Wei Yang Acked-by: Gavin Shan CC: Michael Ellerman V3 -> V4: 1. move the macro definition from include/linux/pci.h to arch/powerpc/include/asm/eeh.h V2 -> V3: 1. rebased on 3.17-rc4 2. introduce a macro 3. use this macro in several other places V1 -> V2: 1. code style and patch subject adjustment Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/eeh.h | 5 +++++ arch/powerpc/kernel/eeh.c | 4 ++-- arch/powerpc/kernel/eeh_pe.c | 2 +- 3 files changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index 9983c3d26bca..757014fe23d3 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -146,6 +146,11 @@ static inline struct pci_dev *eeh_dev_to_pci_dev(struct eeh_dev *edev) return edev ? edev->pdev : NULL; } +static inline struct eeh_pe *eeh_dev_to_pe(struct eeh_dev* edev) +{ + return edev ? edev->pe : NULL; +} + /* Return values from eeh_ops::next_error */ enum { EEH_NEXT_ERR_NONE = 0, diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index 59a64f8dc85f..0f1b63714718 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -410,7 +410,7 @@ int eeh_dev_check_failure(struct eeh_dev *edev) } dn = eeh_dev_to_of_node(edev); dev = eeh_dev_to_pci_dev(edev); - pe = edev->pe; + pe = eeh_dev_to_pe(edev); /* Access to IO BARs might get this far and still not want checking. */ if (!pe) { @@ -634,7 +634,7 @@ int eeh_pci_enable(struct eeh_pe *pe, int function) int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state) { struct eeh_dev *edev = pci_dev_to_eeh_dev(dev); - struct eeh_pe *pe = edev->pe; + struct eeh_pe *pe = eeh_dev_to_pe(edev); if (!pe) { pr_err("%s: No PE found on PCI device %s\n", diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c index 00e3844525a6..5864017e2bd9 100644 --- a/arch/powerpc/kernel/eeh_pe.c +++ b/arch/powerpc/kernel/eeh_pe.c @@ -428,7 +428,7 @@ int eeh_rmv_from_parent_pe(struct eeh_dev *edev) } /* Remove the EEH device */ - pe = edev->pe; + pe = eeh_dev_to_pe(edev); edev->pe = NULL; list_del(&edev->list);