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commit: ff7aef9e665a0417a66e5c92cc5bf1ba7f4c22d3 |
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Author: Bo Yang <boyang <AT> suse <DOT> com> |
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AuthorDate: Wed Aug 29 11:26:11 2012 +0000 |
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Commit: Doug Goldstein <cardoe <AT> gentoo <DOT> org> |
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CommitDate: Wed Oct 24 07:05:04 2012 +0000 |
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URL: http://git.overlays.gentoo.org/gitweb/?p=proj/qemu-kvm.git;a=commit;h=ff7aef9e |
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|
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eepro100: Fix network hang when rx buffers run out |
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|
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This is reported by QA. When installing os with pxe, after the initial |
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kernel and initrd are loaded, the procedure tries to copy files from install |
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server to local harddisk, the network becomes stall because of running out of |
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receive descriptor. |
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|
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[Whitespace fixes and removed qemu_notify_event() because Paolo's |
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earlier net patches have moved it into qemu_flush_queued_packets(). |
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|
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Additional info: |
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|
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I can reproduce the network hang with a tap device doing a iPXE HTTP |
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boot as follows: |
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|
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$ qemu -enable-kvm -m 1024 \ |
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-netdev tap,id=netdev0,script=no,downscript=no \ |
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-device i82559er,netdev=netdev0,romfile=80861209.rom \ |
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-drive if=virtio,cache=none,file=test.img |
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iPXE> ifopen net0 |
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iPXE> config # set static network configuration |
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iPXE> kernel http://mirror.bytemark.co.uk/fedora/linux/releases/17/Fedora/x86_64/os/images/pxeboot/vmlinuz |
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|
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I needed a vanilla iPXE ROM to get to the iPXE prompt. I think the boot |
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prompt has been disabled in the ROMs that ship with QEMU to reduce boot |
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time. |
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|
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During the vmlinuz HTTP download there is a network hang. hw/eepro100.c |
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has reached the end of the rx descriptor list. When the iPXE driver |
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replenishes the rx descriptor list we don't kick the QEMU net subsystem |
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and event loop, thereby leaving the tap netdev without its file |
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descriptor in select(2). |
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|
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Stefan Hajnoczi <stefanha <AT> gmail.com>] |
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|
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Signed-off-by: Bo Yang <boyang <AT> suse.com> |
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Signed-off-by: Stefan Hajnoczi <stefanha <AT> gmail.com> |
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(cherry picked from commit 1069985fb132cd4324fc02d371f1e61492a1823f) |
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|
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--- |
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hw/eepro100.c | 4 +++- |
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1 files changed, 3 insertions(+), 1 deletions(-) |
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|
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diff --git a/hw/eepro100.c b/hw/eepro100.c |
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index 6279ae3..5b62196 100644 |
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--- a/hw/eepro100.c |
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+++ b/hw/eepro100.c |
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@@ -1036,6 +1036,7 @@ static void eepro100_ru_command(EEPRO100State * s, uint8_t val) |
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} |
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set_ru_state(s, ru_ready); |
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s->ru_offset = e100_read_reg4(s, SCBPointer); |
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+ qemu_flush_queued_packets(&s->nic->nc); |
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TRACE(OTHER, logout("val=0x%02x (rx start)\n", val)); |
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break; |
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case RX_RESUME: |
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@@ -1763,7 +1764,8 @@ static ssize_t nic_receive(VLANClientState *nc, const uint8_t * buf, size_t size |
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if (rfd_command & COMMAND_EL) { |
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/* EL bit is set, so this was the last frame. */ |
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logout("receive: Running out of frames\n"); |
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- set_ru_state(s, ru_suspended); |
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+ set_ru_state(s, ru_no_resources); |
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+ eepro100_rnr_interrupt(s); |
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} |
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if (rfd_command & COMMAND_S) { |
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/* S bit is set. */ |
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