From 1ef1142319c7a4f6620b33a8c04f353e5c44cefb Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Thu, 15 Jul 2010 12:11:38 -0300 Subject: [PATCH 1/4] Disable SCSI RH-Author: Markus Armbruster Message-id: Patchwork-id: 10736 O-Subject: [RHEL-6 qemu-kvm PATCH RFC] Disable SCSI Bugzilla: 617534 RH-Acked-by: Luiz Capitulino RH-Acked-by: Amit Shah RH-Acked-by: Gerd Hoffmann Yes, I know how late it is. Lateness is no excuse for letting problematic code drift into the product by inertia. Instead, I want us to weigh pros and cons, then make an informed decision. As far as I know (correct me where I'm wrong): * We actively track and backport fixes to IDE and virtio, but not SCSI. * We test IDE and virtio, but not SCSI. * usb-storage is SCSI under the hood. It doesn't work reliably. * Consequently, we support neither SCSI nor usb-storage. * But we're about to ship them anyway. I think this is a much more serious issue than VLANs: 1. The chief concerns with VLANs are "only" performance and long-term maintainability, not "it may eat your data". 2. VLANs are much less visible to users. It's one thing to have "running /usr/libexec/qemu-kvm is unsupported" in the release notes, but "clicking on SCSI in the virt-manager menu is unsupported" is a different ball game. A user can't reasonably expect that stuff in /usr/libexec is for him to run, so the fine print in the release notes won't catch reasonable users by surprise. But users *can* reasonably expect that menu items are fine to click. 3. Same applies to libvirt API. Users can reasonably expect that stuff available in the supported API actually works. One of the main reasons for keeping VLANs in 6.0 despite they're unsupported is that uses have crept into the product. Are there any known uses of SCSI or usb-storage? For the sake of the argument, let's see how to disable SCSI. The appended patch should do the trick. It touches no code, only makefiles. It drops scsi-disk.o scsi-generic.o scsi-bus.o usb-msd.o lsi53c895a.o pci-hotplug.o. Note that pci-hotplug.o is already 100% dead code. Signed-off-by: Eduardo Habkost --- Makefile | 5 ++--- Makefile.hw | 1 - Makefile.target | 2 +- 3 files changed, 3 insertions(+), 5 deletions(-) diff --git a/Makefile b/Makefile index d147632..878d65f 100644 --- a/Makefile +++ b/Makefile @@ -162,9 +162,8 @@ obj-$(CONFIG_MAX111X) += max111x.o obj-$(CONFIG_DS1338) += ds1338.o obj-y += i2c.o smbus.o smbus_eeprom.o obj-y += eeprom93xx.o -obj-y += scsi-disk.o cdrom.o -obj-y += scsi-generic.o scsi-bus.o -obj-y += usb.o usb-hub.o usb-$(HOST_USB).o usb-hid.o usb-msd.o usb-wacom.o +obj-y += cdrom.o +obj-y += usb.o usb-hub.o usb-$(HOST_USB).o usb-hid.o usb-wacom.o obj-y += usb-serial.o usb-net.o usb-bus.o obj-$(CONFIG_SSI) += ssi.o obj-$(CONFIG_SSI_SD) += ssi-sd.o diff --git a/Makefile.hw b/Makefile.hw index 079c5d2..88a6c1e 100644 --- a/Makefile.hw +++ b/Makefile.hw @@ -37,7 +37,6 @@ obj-$(CONFIG_SMC91C111) += smc91c111.o obj-$(CONFIG_LAN9118) += lan9118.o # SCSI layer -obj-y += lsi53c895a.o obj-$(CONFIG_ESP) += esp.o obj-y += dma-helpers.o sysbus.o isa-bus.o diff --git a/Makefile.target b/Makefile.target index 97b35f5..9e3a369 100644 --- a/Makefile.target +++ b/Makefile.target @@ -210,7 +210,7 @@ obj-i386-y += vga.o vga-pci.o vga-isa.o obj-i386-y += fdc.o mc146818rtc.o serial.o i8259.o i8254.o pcspk.o pc.o obj-i386-y += cirrus_vga.o apic.o ioapic.o parallel.o acpi.o piix_pci.o obj-i386-y += usb-uhci.o vmmouse.o vmport.o vmware_vga.o hpet.o -obj-i386-y += device-hotplug.o pci-hotplug.o smbios.o wdt_ib700.o +obj-i386-y += device-hotplug.o smbios.o wdt_ib700.o obj-i386-y += extboot.o obj-i386-y += ne2000-isa.o obj-i386-y += testdev.o -- 1.7.0.3