- partial PLD merge

[packages/grub2.git] / efi-net-fix.patch

diff --git a/efi-net-fix.patch b/efi-net-fix.patch
new file mode 100644 (file)
index 0000000..41872c0
--- /dev/null
+++ b/efi-net-fix.patch
@@ -0,0 +1,59 @@
+From 886d93184b894a29b0bef1f2467230a20c7a33ce Mon Sep 17 00:00:00 2001
+From: Mark Salter <msalter@redhat.com>
+Date: Tue, 8 Apr 2014 10:58:11 -0400
+Subject: [PATCH] reopen SNP protocol for exclusive use by grub
+
+While working with pxeboot of grub on an ARM platform, I noticed
+very poor network performance while grub was loading a kernel
+and initramfs. The performance during the loading of grub itself
+seemed reasonable. Digging into the issue, I found that the UEFI
+firmware was periodically polling for network packets while grub
+was downloading files. This was causing timeouts and retries in
+the grub network stack.
+
+The solution I found was to reopen the SNP protocol for exclusive
+use. This forces UEFI to shutdown its use of SNP so that grub is
+not competing for incoming packets.
+
+Signed-off-by: Mark Salter <msalter@redhat.com>
+---
+ grub-core/net/drivers/efi/efinet.c | 16 ++++++++++++++++
+ 1 file changed, 16 insertions(+)
+
+diff --git a/grub-core/net/drivers/efi/efinet.c b/grub-core/net/drivers/efi/efinet.c
+index 2b344d6..a6e4c79 100644
+--- a/grub-core/net/drivers/efi/efinet.c
++++ b/grub-core/net/drivers/efi/efinet.c
+@@ -223,6 +223,7 @@ grub_efi_net_config_real (grub_efi_handle_t hnd, char **device,
+ {
+   struct grub_net_card *card;
+   grub_efi_device_path_t *dp;
++  grub_efi_simple_network_t *net;
+ 
+   dp = grub_efi_get_device_path (hnd);
+   if (! dp)
+@@ -250,6 +251,21 @@ grub_efi_net_config_real (grub_efi_handle_t hnd, char **device,
+                                   &pxe_mode->dhcp_ack,
+                                   sizeof (pxe_mode->dhcp_ack),
+                                   1, device, path);
++    net = grub_efi_open_protocol (card->efi_handle, &net_io_guid,
++                                GRUB_EFI_OPEN_PROTOCOL_BY_EXCLUSIVE);
++    if (net) {
++      if (net->mode->state == GRUB_EFI_NETWORK_STOPPED
++        && efi_call_1 (net->start, net) != GRUB_EFI_SUCCESS)
++      continue;
++
++      if (net->mode->state == GRUB_EFI_NETWORK_STOPPED)
++      continue;
++
++      if (net->mode->state == GRUB_EFI_NETWORK_STARTED
++        && efi_call_3 (net->initialize, net, 0, 0) != GRUB_EFI_SUCCESS)
++      continue;
++      card->efi_net = net;
++    }
+     return;
+   }
+ }
+-- 
+1.8.5.3
+