similar to: [PATCH] lib: direct: Disable qemu locking when opening drives

On Tuesday, 5 September 2017 16:55:08 CEST Richard W.M. Jones wrote: > Since qemu 2.10, qemu locks all drives even when they are opened > readonly. This disables this locking in this safe case. > > Incomplete fix for > https://bugzilla.redhat.com/show_bug.cgi?id=1417306 > --- I guess that, according to the other message in this thread, the commit message will be amended to use

Currently we have an OCaml library for generating the qemu command line (used only by ‘virt-v2v -o qemu’). However we also generate a qemu command line in ‘lib/launch-direct.c’, and we might in future need to generate a ‘-readconfig’-compatible configuration file if we want to go beyond 10,000 drives for scalability testing. Therefore this patch series reimplements the qemu command line code as

On Tuesday, 12 September 2017 14:29:16 CEST Richard W.M. Jones wrote: > @@ -255,11 +256,13 @@ add_drive_standard_params (guestfs_h *g, struct backend_direct_data *data, > } > else { > /* Writable qcow2 overlay on top of read-only drive. */ > - append_list_format ("file=%s", drv->overlay); > + append_list_format ("file.file.filename=%s",

Patches 1-4 are almost the same as they are when previously posted here: https://www.redhat.com/archives/libguestfs/2017-September/msg00039.html Patch 5 actually uses the mandatory locking test to turn off locking in the narrow case where a drive is opened readonly, and then only for the drive being inspected. Passes ordinary tests (‘check-direct’ and ‘check-valgrind-direct’). Rich.

Since qemu 2.10, qemu locks all drives even when they are opened readonly. This disables this locking in this safe case. Incomplete fix for https://bugzilla.redhat.com/show_bug.cgi?id=1417306 --- lib/launch-direct.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/lib/launch-direct.c b/lib/launch-direct.c index 3b848165c..e5465539d 100644 --- a/lib/launch-direct.c +++

On Wed, Sep 06, 2017 at 10:41:24AM +0300, Roman Kagan wrote: > On Tue, Sep 05, 2017 at 03:55:08PM +0100, Richard W.M. Jones wrote: > > Since qemu 2.10, qemu locks all drives even when they are opened > > readonly. This disables this locking in this safe case. > > > > Incomplete fix for > > https://bugzilla.redhat.com/show_bug.cgi?id=1417306 > > --- >

v2 -> v3: - I addressed everything that Pino mentioned last time. - It's tricky to get a stable run when multiple copies of qemu are involved, because the same cache files get overwritten by parallel libguestfs. So I changed the names of the cache files to include the qemu binary key (size, mtime), which removes this conflict. This is in new patch 4/6. Rich.

From: Nikolay Ivanets <stenavin@gmail.com> I faced with situation where libguestfs cannot recognize partitions on a disk image which was partitioned on a system with "4K native" sector size support. In order to fix the issue we need to allow users to specify desired physical and/or logical block size per drive basis. It is definitely not a complete patch but rather a way to

Of course I mean state=off (not <htm state=on>) ... Rich.

v1 was here: https://www.redhat.com/archives/libguestfs/2018-September/thread.html#00000 v2: - Make conditional on qemu >= 2.11.2 and libvirt >= 4.6.0. - Fix the libvirt XML to match what went upstream. Still untested. Rich.

When --blocksize <val> is provided, qemu command line would add physical_block_size=<val>,physical_logical_size=<val> to -device directive. Example: qemu-kvm \ -drive file=raw.img,cache=writeback,id=hd0,if=none \ -device scsi-hd,drive=hd0,physical_block_size=4096,logical_block_size=4096 \ Signed-off-by: Tuan Hoang <tmhoang@linux.ibm.com> --- fish/fish.c |

v1 -> v2: - Rebase on top of Pino's version work. Two patches went upstream, these are the two remaining patches. Note the generation number is still inside the qemu.stat file. We could put it in the filename, I have no particular preference. Rich.

Hi, this adds an helper version struct, and uses it in the backends (for the libvirt and qemu versions) and inspection code. This also moves common code to that, so it is not repeated in many places. This should help with the small refactoring proposed with https://www.redhat.com/archives/libguestfs/2016-May/msg00070.html Thanks, Pino Toscano (2): src: start unifying version handling

--- lib/launch-direct.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/lib/launch-direct.c b/lib/launch-direct.c index 9f85013f9..00cb25077 100644 --- a/lib/launch-direct.c +++ b/lib/launch-direct.c @@ -66,6 +66,7 @@ struct backend_direct_data { pid_t recoverypid; /* Recovery process PID. */ struct version qemu_version; /* qemu version (0 if

Ancient qemu 1.5 (in RHEL 7) does not understand the file.file.filename= and file.driver= parameters. Go back to using the old-style file= and format= parameters when we're not trying to set the file.backing.file.locking=off parameter. Fixes commit 9fe592808ccfd9ed184b88ca9c6cad2e1798dee3. Thanks: Yongkui Guo, Václav Kadlčík. --- lib/launch-direct.c | 31 +++++++++++++++++++++---------- 1

Unfortunately I was not able to test this because I don't currently have access to a P9 machine. Rich.

On Sat, Feb 08, 2020 at 01:25:28AM +0200, Mykola Ivanets wrote: > From: Nikolay Ivanets <stenavin@gmail.com> > > I faced with situation where libguestfs cannot recognize partitions on a > disk image which was partitioned on a system with "4K native" sector > size support. > > In order to fix the issue we need to allow users to specify desired > physical

Doing qemu feature detection in the direct backend takes ~100ms because we need to run `qemu -help' and `qemu -devices ?', and each of those interacts with glibc's very slow link loader. Fixing the link loader is really hard. Instead memoize the output of those two commands. This patch series first separates all the code dealing with qemu into a separate module (src/qemu.c) and

This commit uses -bios bios-fast.bin if available, which basically stops SeaBIOS from trying to do PCI probing during boot, which is a waste of time when using the -kernel option. v1 -> v2: - Rebase on top of Pino's work. This still has 3 dependencies: - The qemu memoization work (v2). - Support for '-L ?' in qemu:

QEMU does not accept options unrecognized by the block driver in use. Disable locking only for read-only disks that are file-backed, as that's the only block driver it is supported with. Signed-off-by: Lars Seipel <ls@slrz.net> --- lib/launch-direct.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/lib/launch-direct.c b/lib/launch-direct.c index