Hi Alan, On 07/10/19 11:14 PM, Alan Mikhak wrote: > 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> Thanks for the patch. The change-log title should start with "capitalized verb" linux-pci follows certain guidelines listed here https://lore.kernel.org/r/20171026223701.GA25649@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ Once that gets fixed Acked-by: Kishon Vijay Abraham I <kishon@xxxxxx> >> --- >> 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 Thank you Alan for testing this and sending a patch to fix it. Cheers Kishon
