* [Qemu-devel] Windows balloon driver PFN issue @ 2018-01-31 9:28 Peter Xu 2018-01-31 14:03 ` Michael S. Tsirkin 0 siblings, 1 reply; 8+ messages in thread From: Peter Xu @ 2018-01-31 9:28 UTC (permalink / raw) To: QEMU Devel Mailing List, Michael S. Tsirkin Hi, Michael and the list, I observed this on windows 8 enterprise guests, when doing memory ballooning: 23892@1517298572.328354:virtio_balloon_to_target balloon target: 0x80000000 num_pages: 524288 23892@1517298638.542819:virtio_balloon_get_config num_pages: 524288 actual: 0 23892@1517298638.542974:virtio_balloon_handle_output section name: pc.ram gpa: 0x174604000 23892@1517298638.543059:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 23892@1517298638.543135:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460a000 23892@1517298638.543140:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 23892@1517298638.543143:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460b000 23892@1517298638.543146:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 23892@1517298638.543148:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460c000 23892@1517298638.543152:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 23892@1517298638.543154:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460d000 23892@1517298638.543159:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 23892@1517298638.543162:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460e000 23892@1517298638.543165:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 23892@1517298638.543167:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460f000 23892@1517298638.543170:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 ... I think it's very possible that these zero addresses (please let me know what the first 4K page is used for if anyone knows, since IIUC that's what we throw away now) are half of the 64bit PFN. Or say, not sure whether this means a windows guest driver bug that is using 64bits for PFN rather than 32bits (and I suppose the protocol is using 32bit for PFNs). Michael, do you know what to do with this? Thanks, -- Peter Xu ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [Qemu-devel] Windows balloon driver PFN issue 2018-01-31 9:28 [Qemu-devel] Windows balloon driver PFN issue Peter Xu @ 2018-01-31 14:03 ` Michael S. Tsirkin 2018-02-01 2:18 ` Peter Xu 0 siblings, 1 reply; 8+ messages in thread From: Michael S. Tsirkin @ 2018-01-31 14:03 UTC (permalink / raw) To: Peter Xu; +Cc: QEMU Devel Mailing List On Wed, Jan 31, 2018 at 05:28:35PM +0800, Peter Xu wrote: > Hi, Michael and the list, > > I observed this on windows 8 enterprise guests, when doing memory ballooning: > > 23892@1517298572.328354:virtio_balloon_to_target balloon target: 0x80000000 num_pages: 524288 > 23892@1517298638.542819:virtio_balloon_get_config num_pages: 524288 actual: 0 > 23892@1517298638.542974:virtio_balloon_handle_output section name: pc.ram gpa: 0x174604000 > 23892@1517298638.543059:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > 23892@1517298638.543135:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460a000 > 23892@1517298638.543140:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > 23892@1517298638.543143:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460b000 > 23892@1517298638.543146:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > 23892@1517298638.543148:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460c000 > 23892@1517298638.543152:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > 23892@1517298638.543154:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460d000 > 23892@1517298638.543159:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > 23892@1517298638.543162:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460e000 > 23892@1517298638.543165:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > 23892@1517298638.543167:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460f000 > 23892@1517298638.543170:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > ... > > I think it's very possible that these zero addresses (please let me > know what the first 4K page is used for if anyone knows, since IIUC > that's what we throw away now) are half of the 64bit PFN. Or say, not > sure whether this means a windows guest driver bug that is using > 64bits for PFN rather than 32bits (and I suppose the protocol is using > 32bit for PFNs). > > Michael, do you know what to do with this? > > Thanks, PFN is GPA>>12. Do you have more than 1<<44 bytes of memory in this VM then? > -- > Peter Xu ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [Qemu-devel] Windows balloon driver PFN issue 2018-01-31 14:03 ` Michael S. Tsirkin @ 2018-02-01 2:18 ` Peter Xu 2018-02-01 2:24 ` Michael S. Tsirkin 0 siblings, 1 reply; 8+ messages in thread From: Peter Xu @ 2018-02-01 2:18 UTC (permalink / raw) To: Michael S. Tsirkin; +Cc: QEMU Devel Mailing List On Wed, Jan 31, 2018 at 04:03:12PM +0200, Michael S. Tsirkin wrote: > On Wed, Jan 31, 2018 at 05:28:35PM +0800, Peter Xu wrote: > > Hi, Michael and the list, > > > > I observed this on windows 8 enterprise guests, when doing memory ballooning: > > > > 23892@1517298572.328354:virtio_balloon_to_target balloon target: 0x80000000 num_pages: 524288 > > 23892@1517298638.542819:virtio_balloon_get_config num_pages: 524288 actual: 0 > > 23892@1517298638.542974:virtio_balloon_handle_output section name: pc.ram gpa: 0x174604000 > > 23892@1517298638.543059:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > 23892@1517298638.543135:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460a000 > > 23892@1517298638.543140:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > 23892@1517298638.543143:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460b000 > > 23892@1517298638.543146:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > 23892@1517298638.543148:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460c000 > > 23892@1517298638.543152:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > 23892@1517298638.543154:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460d000 > > 23892@1517298638.543159:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > 23892@1517298638.543162:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460e000 > > 23892@1517298638.543165:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > 23892@1517298638.543167:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460f000 > > 23892@1517298638.543170:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > ... > > > > I think it's very possible that these zero addresses (please let me > > know what the first 4K page is used for if anyone knows, since IIUC > > that's what we throw away now) are half of the 64bit PFN. Or say, not > > sure whether this means a windows guest driver bug that is using > > 64bits for PFN rather than 32bits (and I suppose the protocol is using > > 32bit for PFNs). > > > > Michael, do you know what to do with this? > > > > Thanks, > > PFN is GPA>>12. Do you have more than 1<<44 bytes of memory in this VM then? No. But isn't it still not good to drop the page at offset zero (and drop it NNN times)? And I'm not sure what will happen if guest has 1<<44 bytes; then we'll possibly drop very random addresses since a real address will be splitted? Thanks, -- Peter Xu ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [Qemu-devel] Windows balloon driver PFN issue 2018-02-01 2:18 ` Peter Xu @ 2018-02-01 2:24 ` Michael S. Tsirkin 2018-02-01 2:33 ` Peter Xu 0 siblings, 1 reply; 8+ messages in thread From: Michael S. Tsirkin @ 2018-02-01 2:24 UTC (permalink / raw) To: Peter Xu; +Cc: QEMU Devel Mailing List On Thu, Feb 01, 2018 at 10:18:53AM +0800, Peter Xu wrote: > On Wed, Jan 31, 2018 at 04:03:12PM +0200, Michael S. Tsirkin wrote: > > On Wed, Jan 31, 2018 at 05:28:35PM +0800, Peter Xu wrote: > > > Hi, Michael and the list, > > > > > > I observed this on windows 8 enterprise guests, when doing memory ballooning: > > > > > > 23892@1517298572.328354:virtio_balloon_to_target balloon target: 0x80000000 num_pages: 524288 > > > 23892@1517298638.542819:virtio_balloon_get_config num_pages: 524288 actual: 0 > > > 23892@1517298638.542974:virtio_balloon_handle_output section name: pc.ram gpa: 0x174604000 > > > 23892@1517298638.543059:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > 23892@1517298638.543135:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460a000 > > > 23892@1517298638.543140:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > 23892@1517298638.543143:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460b000 > > > 23892@1517298638.543146:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > 23892@1517298638.543148:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460c000 > > > 23892@1517298638.543152:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > 23892@1517298638.543154:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460d000 > > > 23892@1517298638.543159:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > 23892@1517298638.543162:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460e000 > > > 23892@1517298638.543165:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > 23892@1517298638.543167:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460f000 > > > 23892@1517298638.543170:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > ... > > > > > > I think it's very possible that these zero addresses (please let me > > > know what the first 4K page is used for if anyone knows, since IIUC > > > that's what we throw away now) are half of the 64bit PFN. Or say, not > > > sure whether this means a windows guest driver bug that is using > > > 64bits for PFN rather than 32bits (and I suppose the protocol is using > > > 32bit for PFNs). > > > > > > Michael, do you know what to do with this? > > > > > > Thanks, > > > > PFN is GPA>>12. Do you have more than 1<<44 bytes of memory in this VM then? > > No. But isn't it still not good to drop the page at offset zero (and > drop it NNN times)? Absolutely - looks like a bug. I just don't know why does this happen. > And I'm not sure what will happen if guest has > 1<<44 bytes; then we'll possibly drop very random addresses since a > real address will be splitted? > > Thanks, The balloon won't work, period. There was an interface change to fix that but implementation issues remained and contributor seems to be busy with page hints. > -- > Peter Xu ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [Qemu-devel] Windows balloon driver PFN issue 2018-02-01 2:24 ` Michael S. Tsirkin @ 2018-02-01 2:33 ` Peter Xu 2018-02-01 12:48 ` Michael S. Tsirkin 0 siblings, 1 reply; 8+ messages in thread From: Peter Xu @ 2018-02-01 2:33 UTC (permalink / raw) To: Michael S. Tsirkin; +Cc: QEMU Devel Mailing List On Thu, Feb 01, 2018 at 04:24:40AM +0200, Michael S. Tsirkin wrote: > On Thu, Feb 01, 2018 at 10:18:53AM +0800, Peter Xu wrote: > > On Wed, Jan 31, 2018 at 04:03:12PM +0200, Michael S. Tsirkin wrote: > > > On Wed, Jan 31, 2018 at 05:28:35PM +0800, Peter Xu wrote: > > > > Hi, Michael and the list, > > > > > > > > I observed this on windows 8 enterprise guests, when doing memory ballooning: > > > > > > > > 23892@1517298572.328354:virtio_balloon_to_target balloon target: 0x80000000 num_pages: 524288 > > > > 23892@1517298638.542819:virtio_balloon_get_config num_pages: 524288 actual: 0 > > > > 23892@1517298638.542974:virtio_balloon_handle_output section name: pc.ram gpa: 0x174604000 > > > > 23892@1517298638.543059:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > 23892@1517298638.543135:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460a000 > > > > 23892@1517298638.543140:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > 23892@1517298638.543143:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460b000 > > > > 23892@1517298638.543146:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > 23892@1517298638.543148:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460c000 > > > > 23892@1517298638.543152:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > 23892@1517298638.543154:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460d000 > > > > 23892@1517298638.543159:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > 23892@1517298638.543162:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460e000 > > > > 23892@1517298638.543165:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > 23892@1517298638.543167:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460f000 > > > > 23892@1517298638.543170:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > ... > > > > > > > > I think it's very possible that these zero addresses (please let me > > > > know what the first 4K page is used for if anyone knows, since IIUC > > > > that's what we throw away now) are half of the 64bit PFN. Or say, not > > > > sure whether this means a windows guest driver bug that is using > > > > 64bits for PFN rather than 32bits (and I suppose the protocol is using > > > > 32bit for PFNs). > > > > > > > > Michael, do you know what to do with this? > > > > > > > > Thanks, > > > > > > PFN is GPA>>12. Do you have more than 1<<44 bytes of memory in this VM then? > > > > No. But isn't it still not good to drop the page at offset zero (and > > drop it NNN times)? > > Absolutely - looks like a bug. I just don't know why does this happen. IMHO if we are using a PFN array like this: u64 pfn_array[]; In the windows guest driver, then we'll see this (as mentioned above). But for sure this is wild guess of mine. > > > And I'm not sure what will happen if guest has > > 1<<44 bytes; then we'll possibly drop very random addresses since a > > real address will be splitted? > > > > Thanks, > > The balloon won't work, period. There was an interface change to fix > that but implementation issues remained and contributor seems to be busy > with page hints. Okay. So IIUC this is already a known issue for the driver owner. Then it seems that there's nothing more I can do for now... Thanks, -- Peter Xu ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [Qemu-devel] Windows balloon driver PFN issue 2018-02-01 2:33 ` Peter Xu @ 2018-02-01 12:48 ` Michael S. Tsirkin 2018-02-02 10:11 ` Peter Xu 0 siblings, 1 reply; 8+ messages in thread From: Michael S. Tsirkin @ 2018-02-01 12:48 UTC (permalink / raw) To: Peter Xu; +Cc: QEMU Devel Mailing List On Thu, Feb 01, 2018 at 10:33:50AM +0800, Peter Xu wrote: > On Thu, Feb 01, 2018 at 04:24:40AM +0200, Michael S. Tsirkin wrote: > > On Thu, Feb 01, 2018 at 10:18:53AM +0800, Peter Xu wrote: > > > On Wed, Jan 31, 2018 at 04:03:12PM +0200, Michael S. Tsirkin wrote: > > > > On Wed, Jan 31, 2018 at 05:28:35PM +0800, Peter Xu wrote: > > > > > Hi, Michael and the list, > > > > > > > > > > I observed this on windows 8 enterprise guests, when doing memory ballooning: > > > > > > > > > > 23892@1517298572.328354:virtio_balloon_to_target balloon target: 0x80000000 num_pages: 524288 > > > > > 23892@1517298638.542819:virtio_balloon_get_config num_pages: 524288 actual: 0 > > > > > 23892@1517298638.542974:virtio_balloon_handle_output section name: pc.ram gpa: 0x174604000 > > > > > 23892@1517298638.543059:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > > 23892@1517298638.543135:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460a000 > > > > > 23892@1517298638.543140:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > > 23892@1517298638.543143:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460b000 > > > > > 23892@1517298638.543146:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > > 23892@1517298638.543148:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460c000 > > > > > 23892@1517298638.543152:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > > 23892@1517298638.543154:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460d000 > > > > > 23892@1517298638.543159:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > > 23892@1517298638.543162:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460e000 > > > > > 23892@1517298638.543165:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > > 23892@1517298638.543167:virtio_balloon_handle_output section name: pc.ram gpa: 0x17460f000 > > > > > 23892@1517298638.543170:virtio_balloon_handle_output section name: pc.ram gpa: 0x0 > > > > > ... > > > > > > > > > > I think it's very possible that these zero addresses (please let me > > > > > know what the first 4K page is used for if anyone knows, since IIUC > > > > > that's what we throw away now) are half of the 64bit PFN. Or say, not > > > > > sure whether this means a windows guest driver bug that is using > > > > > 64bits for PFN rather than 32bits (and I suppose the protocol is using > > > > > 32bit for PFNs). > > > > > > > > > > Michael, do you know what to do with this? > > > > > > > > > > Thanks, > > > > > > > > PFN is GPA>>12. Do you have more than 1<<44 bytes of memory in this VM then? > > > > > > No. But isn't it still not good to drop the page at offset zero (and > > > drop it NNN times)? > > > > Absolutely - looks like a bug. I just don't know why does this happen. > > IMHO if we are using a PFN array like this: > > u64 pfn_array[]; > > In the windows guest driver, then we'll see this (as mentioned > above). But for sure this is wild guess of mine. I don't see code like this anywhere in the windows balloon driver. It's here: https://github.com/virtio-win/kvm-guest-drivers-windows.git > > > > > And I'm not sure what will happen if guest has > > > 1<<44 bytes; then we'll possibly drop very random addresses since a > > > real address will be splitted? > > > > > > Thanks, > > > > The balloon won't work, period. There was an interface change to fix > > that but implementation issues remained and contributor seems to be busy > > with page hints. > > Okay. So IIUC this is already a known issue for the driver owner. > Then it seems that there's nothing more I can do for now... > > Thanks, > > -- > Peter Xu ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [Qemu-devel] Windows balloon driver PFN issue 2018-02-01 12:48 ` Michael S. Tsirkin @ 2018-02-02 10:11 ` Peter Xu [not found] ` <CAA2ifQzRFsZ_=mr9WrFjieTS7YuzQdz5xhoEWOE-5pWWBhBD7Q@mail.gmail.com> 0 siblings, 1 reply; 8+ messages in thread From: Peter Xu @ 2018-02-02 10:11 UTC (permalink / raw) To: Michael S. Tsirkin; +Cc: QEMU Devel Mailing List On Thu, Feb 01, 2018 at 02:48:20PM +0200, Michael S. Tsirkin wrote: [...] > > > > > PFN is GPA>>12. Do you have more than 1<<44 bytes of memory in this VM then? > > > > > > > > No. But isn't it still not good to drop the page at offset zero (and > > > > drop it NNN times)? > > > > > > Absolutely - looks like a bug. I just don't know why does this happen. > > > > IMHO if we are using a PFN array like this: > > > > u64 pfn_array[]; > > > > In the windows guest driver, then we'll see this (as mentioned > > above). But for sure this is wild guess of mine. > > I don't see code like this anywhere in the windows balloon > driver. It's here: > https://github.com/virtio-win/kvm-guest-drivers-windows.git Thanks for the pointer. I had a quick glance, the PFN array is defined as: PPFN_NUMBER pfns_table; But I don't know what's sizeof(PPFN_NUMBER). :( -- Peter Xu ^ permalink raw reply [flat|nested] 8+ messages in thread
[parent not found: <CAA2ifQzRFsZ_=mr9WrFjieTS7YuzQdz5xhoEWOE-5pWWBhBD7Q@mail.gmail.com>]
* Re: [Qemu-devel] Windows balloon driver PFN issue [not found] ` <CAA2ifQzRFsZ_=mr9WrFjieTS7YuzQdz5xhoEWOE-5pWWBhBD7Q@mail.gmail.com> @ 2018-02-27 2:59 ` Peter Xu 0 siblings, 0 replies; 8+ messages in thread From: Peter Xu @ 2018-02-27 2:59 UTC (permalink / raw) To: Gal Hammer; +Cc: QEMU Devel Mailing List, Michael S. Tsirkin On Mon, Feb 26, 2018 at 10:54:11AM +0200, Gal Hammer wrote: > Hi Peter, > > On Fri, Feb 2, 2018 at 12:11 PM, Peter Xu <peterx@redhat.com> wrote: > > On Thu, Feb 01, 2018 at 02:48:20PM +0200, Michael S. Tsirkin wrote: > > > > [...] > > > >> > > > > PFN is GPA>>12. Do you have more than 1<<44 bytes of memory in this VM then? > >> > > > > >> > > > No. But isn't it still not good to drop the page at offset zero (and > >> > > > drop it NNN times)? > >> > > > >> > > Absolutely - looks like a bug. I just don't know why does this happen. > >> > > >> > IMHO if we are using a PFN array like this: > >> > > >> > u64 pfn_array[]; > >> > > >> > In the windows guest driver, then we'll see this (as mentioned > >> > above). But for sure this is wild guess of mine. > >> > >> I don't see code like this anywhere in the windows balloon > >> driver. It's here: > >> https://github.com/virtio-win/kvm-guest-drivers-windows.git > > > > Thanks for the pointer. I had a quick glance, the PFN array is > > defined as: > > > > PPFN_NUMBER pfns_table; > > > > But I don't know what's sizeof(PPFN_NUMBER). :( > > sizeof(PPFN_NUMBER) = sizeof(void*) > > PFN_NUMBER is of an unsigned long type. Although it doesn't matter, as > a pointer to it is always the same size, 4 bytes in a 32-bit CPU and 8 > bytes in 64-bit one. Ah, it's not really PPFN_NUMBER that matters, it should be PFN_NUMBER. This is how the PFNs are copied in windows driver: RtlCopyMemory(ctx->pfns_table, MmGetMdlPfnArray(pPageMdl), ctx->num_pfns * sizeof(PFN_NUMBER)); I don't know these APIs, but it looks like MmGetMdlPfnArray() is returning an PFN_NUMBER array. And I don't know how the balloon spec says, but in QEMU it's always using uint32_t as PFN. See virtio_balloon_handle_output(): while (iov_to_buf(elem->out_sg, elem->out_num, offset, &pfn, 4) == 4) So I guess only if sizeof(PFN_NUMBER)==4 is true on both 32/64 bits platforms of windows, otherwise there might be a problem. Thanks, -- Peter Xu ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2018-02-27 3:00 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-01-31 9:28 [Qemu-devel] Windows balloon driver PFN issue Peter Xu
2018-01-31 14:03 ` Michael S. Tsirkin
2018-02-01 2:18 ` Peter Xu
2018-02-01 2:24 ` Michael S. Tsirkin
2018-02-01 2:33 ` Peter Xu
2018-02-01 12:48 ` Michael S. Tsirkin
2018-02-02 10:11 ` Peter Xu
[not found] ` <CAA2ifQzRFsZ_=mr9WrFjieTS7YuzQdz5xhoEWOE-5pWWBhBD7Q@mail.gmail.com>
2018-02-27 2:59 ` Peter Xu
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).