| Message ID | 20210914015326.1494-3-jiangkunkun@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vfio: Some fixes about vfio-pci MMIO RAM mapping | expand |
Hi Kunkun, On 9/14/21 3:53 AM, Kunkun Jiang wrote: > The MSI-X structures of some devices and other non-MSI-X structures > are in the same BAR. They may share one host page, especially in the may be in the same bar? > case of large page granularity, such as 64K. > > For example, MSIX-Table size of 82599 NIC is 0x30 and the offset in > Bar 3(size 64KB) is 0x0. If host page size is 64KB. remove the '.' In that case wouldn't the symptom be the same with a 4kB page? > vfio_listener_region_add() will be called to map the remaining range > (0x30-0xffff). And it will return early at > 'int128_ge((int128_make64(iova), llend))' and hasn't any message. s/and hasn't any message /without any message > Let's add a trace point to informed users like commit 5c08600547c0 s/informed/inform > ("vfio: Use a trace point when a RAM section cannot be DMA mapped") > did. > > Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> > --- > hw/vfio/common.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/hw/vfio/common.c b/hw/vfio/common.c > index 8728d4d5c2..2fc6213c0f 100644 > --- a/hw/vfio/common.c > +++ b/hw/vfio/common.c > @@ -892,6 +892,13 @@ static void vfio_listener_region_add(MemoryListener *listener, > llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask)); > > if (int128_ge(int128_make64(iova), llend)) { > + if (memory_region_is_ram_device(section->mr)) { > + trace_vfio_listener_region_add_no_dma_map( > + memory_region_name(section->mr), > + section->offset_within_address_space, > + int128_getlo(section->size), > + qemu_real_host_page_size); > + } > return; > } > end = int128_get64(int128_sub(llend, int128_one())); Thanks Eric
Hi Eric, On 2021/10/22 1:02, Eric Auger wrote: > Hi Kunkun, > > On 9/14/21 3:53 AM, Kunkun Jiang wrote: >> The MSI-X structures of some devices and other non-MSI-X structures >> are in the same BAR. They may share one host page, especially in the > may be in the same bar? You are right. So embarrassing.
diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 8728d4d5c2..2fc6213c0f 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -892,6 +892,13 @@ static void vfio_listener_region_add(MemoryListener *listener, llend = int128_and(llend, int128_exts64(qemu_real_host_page_mask)); if (int128_ge(int128_make64(iova), llend)) { + if (memory_region_is_ram_device(section->mr)) { + trace_vfio_listener_region_add_no_dma_map( + memory_region_name(section->mr), + section->offset_within_address_space, + int128_getlo(section->size), + qemu_real_host_page_size); + } return; } end = int128_get64(int128_sub(llend, int128_one()));
The MSI-X structures of some devices and other non-MSI-X structures are in the same BAR. They may share one host page, especially in the case of large page granularity, such as 64K. For example, MSIX-Table size of 82599 NIC is 0x30 and the offset in Bar 3(size 64KB) is 0x0. If host page size is 64KB. vfio_listener_region_add() will be called to map the remaining range (0x30-0xffff). And it will return early at 'int128_ge((int128_make64(iova), llend))' and hasn't any message. Let's add a trace point to informed users like commit 5c08600547c0 ("vfio: Use a trace point when a RAM section cannot be DMA mapped") did. Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> --- hw/vfio/common.c | 7 +++++++ 1 file changed, 7 insertions(+)