From: Cédric Le Goater clg@kaod.org
commit b67a95f2abff0c34e5667c15ab8900de73d8d087 upstream.
The PCI INTx interrupts and other LSI interrupts are handled differently under a sPAPR platform. When the interrupt source characteristics are queried, the hypervisor returns an H_INT_ESB flag to inform the OS that it should be using the H_INT_ESB hcall for interrupt management and not loads and stores on the interrupt ESB pages.
A default -1 value is returned for the addresses of the ESB pages. The driver ignores this condition today and performs a bogus IO mapping. Recent changes and the DEBUG_VM configuration option make the bug visible with :
kernel BUG at arch/powerpc/include/asm/book3s/64/pgtable.h:612! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Radix MMU=Hash SMP NR_CPUS=1024 NUMA pSeries Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.4.0-0.rc6.git0.1.fc32.ppc64le #1 NIP: c000000000f63294 LR: c000000000f62e44 CTR: 0000000000000000 REGS: c0000000fa45f0d0 TRAP: 0700 Not tainted (5.4.0-0.rc6.git0.1.fc32.ppc64le) ... NIP ioremap_page_range+0x4c4/0x6e0 LR ioremap_page_range+0x74/0x6e0 Call Trace: ioremap_page_range+0x74/0x6e0 (unreliable) do_ioremap+0x8c/0x120 __ioremap_caller+0x128/0x140 ioremap+0x30/0x50 xive_spapr_populate_irq_data+0x170/0x260 xive_irq_domain_map+0x8c/0x170 irq_domain_associate+0xb4/0x2d0 irq_create_mapping+0x1e0/0x3b0 irq_create_fwspec_mapping+0x27c/0x3e0 irq_create_of_mapping+0x98/0xb0 of_irq_parse_and_map_pci+0x168/0x230 pcibios_setup_device+0x88/0x250 pcibios_setup_bus_devices+0x54/0x100 __of_scan_bus+0x160/0x310 pcibios_scan_phb+0x330/0x390 pcibios_init+0x8c/0x128 do_one_initcall+0x60/0x2c0 kernel_init_freeable+0x290/0x378 kernel_init+0x2c/0x148 ret_from_kernel_thread+0x5c/0x80
Fixes: bed81ee181dd ("powerpc/xive: introduce H_INT_ESB hcall") Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Cédric Le Goater clg@kaod.org Tested-by: Daniel Axtens dja@axtens.net Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20191203163642.2428-1-clg@kaod.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/powerpc/sysdev/xive/spapr.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)
--- a/arch/powerpc/sysdev/xive/spapr.c +++ b/arch/powerpc/sysdev/xive/spapr.c @@ -392,20 +392,28 @@ static int xive_spapr_populate_irq_data( data->esb_shift = esb_shift; data->trig_page = trig_page;
+ data->hw_irq = hw_irq; + /* * No chip-id for the sPAPR backend. This has an impact how we * pick a target. See xive_pick_irq_target(). */ data->src_chip = XIVE_INVALID_CHIP_ID;
+ /* + * When the H_INT_ESB flag is set, the H_INT_ESB hcall should + * be used for interrupt management. Skip the remapping of the + * ESB pages which are not available. + */ + if (data->flags & XIVE_IRQ_FLAG_H_INT_ESB) + return 0; + data->eoi_mmio = ioremap(data->eoi_page, 1u << data->esb_shift); if (!data->eoi_mmio) { pr_err("Failed to map EOI page for irq 0x%x\n", hw_irq); return -ENOMEM; }
- data->hw_irq = hw_irq; - /* Full function page supports trigger */ if (flags & XIVE_SRC_TRIGGER) { data->trig_mmio = data->eoi_mmio;