On Fri, Oct 4, 2019 at 6:49 PM Alan Mikhak <alan.mikhak@xxxxxxxxxx> wrote: > > From: Alan Mikhak <alan.mikhak@xxxxxxxxxx> > > Modify pci_epc_mem_alloc_addr() to cast the variable 'pageno' > from type 'int' to 'phys_addr_t' before shifting left. This > cast is needed to avoid treating bit 31 of 'pageno' as the > sign bit which would otherwise get sign-extended to produce > a negative value. When added to the base address of PCI memory > space, the negative value would produce an invalid physical > address which falls before the start of the PCI memory space. > > Signed-off-by: Alan Mikhak <alan.mikhak@xxxxxxxxxx> > --- > drivers/pci/endpoint/pci-epc-mem.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c > index 2bf8bd1f0563..d2b174ce15de 100644 > --- a/drivers/pci/endpoint/pci-epc-mem.c > +++ b/drivers/pci/endpoint/pci-epc-mem.c > @@ -134,7 +134,7 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, > if (pageno < 0) > return NULL; > > - *phys_addr = mem->phys_base + (pageno << page_shift); > + *phys_addr = mem->phys_base + ((phys_addr_t)pageno << page_shift); > virt_addr = ioremap(*phys_addr, size); > if (!virt_addr) > bitmap_release_region(mem->bitmap, pageno, order); > -- > 2.7.4 > Hi Kishon, This issue was observed when requesting pci_epc_mem_alloc_addr() to allocate a region of size 0x40010000ULL (1GB + 64KB) from a 128GB PCI address space with page sizes being 64KB. This resulted in 'pageno' value of '0x8000' as the first available page in a contiguous region for the requested size due to other smaller regions having been allocated earlier. With 64KB page sizes, the variable 'page_shift' holds a value of 0x10. Shifting 'pageno' 16 bits to the left results in an 'int' value whose bit 31 is set. [ 10.565256] __pci_epc_mem_init: mem size 0x2000000000 page_size 0x10000 [ 10.571613] __pci_epc_mem_init: mem pages 0x200000 bitmap_size 0x40000 page_shift 0x10 PCI memory base 0x2000000000 PCI memory size 128M 0x2000000000 page_size 64K 0x10000 page_shift 16 0x10 pages 2M 0x200000 bitmap_size 256K 0x40000 [ 702.050299] pci_epc_mem_alloc_addr: size 0x10000 order 0x0 pageno 0x4 virt_add 0xffffffd0047b0000 phys_addr 0x2000040000 [ 702.061424] pci_epc_mem_alloc_addr: size 0x10000 order 0x0 pageno 0x5 virt_add 0xffffffd0047d0000 phys_addr 0x2000050000 [ 702.203933] pci_epc_mem_alloc_addr: size 0x40010000 order 0xf pageno 0x8000 virt_add 0xffffffd004800000 phys_addr 0x1f80000000 [ 702.216547] Oops - store (or AMO) access fault [#1] ::: [ 702.310198] sstatus: 0000000200000120 sbadaddr: ffffffd004804000 scause: 0000000000000007 Regards, Alan
