Hi all, ping... Sorry to disturb, but any comment about this patchset? Thanks Yisheng On 2018/3/31 15:12, Yisheng Xie wrote: > Zhou reported a bug on Hisilicon arm64 D06 platform with 64KB page size: > > [ 2.470908] kernel BUG at lib/ioremap.c:72! > [ 2.475079] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP > [ 2.480551] Modules linked in: > [ 2.483594] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.16.0-rc7-00062-g0b41260-dirty #23 > [ 2.491756] Hardware name: Huawei D06/D06, BIOS Hisilicon D06 UEFI Nemo 2.0 RC0 - B120 03/23/2018 > [ 2.500614] pstate: 80c00009 (Nzcv daif +PAN +UAO) > [ 2.505395] pc : ioremap_page_range+0x268/0x36c > [ 2.509912] lr : pci_remap_iospace+0xe4/0x100 > [...] > [ 2.603733] Call trace: > [ 2.606168] ioremap_page_range+0x268/0x36c > [ 2.610337] pci_remap_iospace+0xe4/0x100 > [ 2.614334] acpi_pci_probe_root_resources+0x1d4/0x214 > [ 2.619460] pci_acpi_root_prepare_resources+0x18/0xa8 > [ 2.624585] acpi_pci_root_create+0x98/0x214 > [ 2.628843] pci_acpi_scan_root+0x124/0x20c > [ 2.633013] acpi_pci_root_add+0x224/0x494 > [ 2.637096] acpi_bus_attach+0xf8/0x200 > [ 2.640918] acpi_bus_attach+0x98/0x200 > [ 2.644740] acpi_bus_attach+0x98/0x200 > [ 2.648562] acpi_bus_scan+0x48/0x9c > [ 2.652125] acpi_scan_init+0x104/0x268 > [ 2.655948] acpi_init+0x308/0x374 > [ 2.659337] do_one_initcall+0x48/0x14c > [ 2.663160] kernel_init_freeable+0x19c/0x250 > [ 2.667504] kernel_init+0x10/0x100 > [ 2.670979] ret_from_fork+0x10/0x18 > > The cause is the size of PCI IO resource is 32KB, which is 4K aligned but > not 64KB aligned, however, ioremap_page_range() request the range as page > aligned or it will trigger a BUG_ON() on ioremap_pte_range() it calls, as > ioremap_pte_range increase the addr by PAGE_SIZE, which makes addr != end > until trigger BUG_ON, if its incoming end is not page aligned. More detail > trace is as following: > > ioremap_page_range > -> ioremap_p4d_range > -> ioremap_p4d_range > -> ioremap_pud_range > -> ioremap_pmd_range > -> ioremap_pte_range > > This patch fix the bug by align the size of PCI IO resource to PAGE_SIZE. > > Reported-by: Zhou Wang <wangzhou1@xxxxxxxxxxxxx> > Tested-by: Xiaojun Tan <tanxiaojun@xxxxxxxxxx> > Signed-off-by: Yisheng Xie <xieyisheng1@xxxxxxxxxx> > --- > I mark this as v2 for I have post a RFC version: > > https://lkml.org/lkml/2018/3/30/8 > > v2: > * Let the caller of ioremap_page_range() align the request by PAGE_SIZE - per Toshi > > Thanks > Yisheng > > drivers/acpi/pci_root.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c > index 6fc204a..b758ca3 100644 > --- a/drivers/acpi/pci_root.c > +++ b/drivers/acpi/pci_root.c > @@ -746,7 +746,7 @@ static void acpi_pci_root_remap_iospace(struct resource_entry *entry) > goto err; > > res->start = port; > - res->end = port + length - 1; > + res->end = PAGE_ALIGN(port + length) - 1; > entry->offset = port - pci_addr; > > if (pci_remap_iospace(res, cpu_addr) < 0) >
