Blame SOURCES/kvm-virtiofsd-Disable-remote-posix-locks-by-default.patch

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From 3ec945ba7c2649cca13cf6070c6365b1262ad1ec Mon Sep 17 00:00:00 2001
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From: Max Reitz <mreitz@redhat.com>
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Date: Fri, 6 Aug 2021 11:58:26 -0400
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Subject: [PATCH 1/2] virtiofsd: Disable remote posix locks by default
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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RH-Author: Max Reitz <mreitz@redhat.com>
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Message-id: <20210806115827.740945-2-mreitz@redhat.com>
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Patchwork-id: 101970
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O-Subject: [RHEL-8.5.0 qemu-kvm PATCH 1/2] virtiofsd: Disable remote posix locks by default
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Bugzilla: 1967496
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RH-Acked-by: Stefano Garzarella <sgarzare@redhat.com>
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RH-Acked-by: Philippe Mathieu-Daudé <philmd@redhat.com>
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RH-Acked-by: Vivek Goyal <vgoyal@redhat.com>
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From: Vivek Goyal <vgoyal@redhat.com>
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Right now we enable remote posix locks by default. That means when guest
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does a posix lock it sends request to server (virtiofsd). But currently
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we only support non-blocking posix lock and return -EOPNOTSUPP for
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blocking version.
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This means that existing applications which are doing blocking posix
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locks get -EOPNOTSUPP and fail. To avoid this, people have been
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running virtiosd with option "-o no_posix_lock". For new users it
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is still a surprise and trial and error takes them to this option.
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Given posix lock implementation is not complete in virtiofsd, disable
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it by default. This means that posix locks will work with-in applications
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in a guest but not across guests. Anyway we don't support sharing
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filesystem among different guests yet in virtiofs so this should
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not lead to any kind of surprise or regression and will make life
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little easier for virtiofs users.
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Reported-by: Aa Aa <jimbothom@yandex.com>
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Suggested-by: Miklos Szeredi <mszeredi@redhat.com>
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Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
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Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
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Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
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Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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(cherry picked from commit 88fc107956a5812649e5918e0c092d3f78bb28ad)
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Conflicts:
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	docs/tools/virtiofsd.rst
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	We do not have virtiofsd.rst downstream (added upstream in
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	commit 6a7e2bbee5fa), so I dropped that hunk (which effectively
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	updated the default value in the man page).
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Signed-off-by: Max Reitz <mreitz@redhat.com>
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Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
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---
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 tools/virtiofsd/passthrough_ll.c | 2 +-
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 1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
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index cb0992f2db..b47029da89 100644
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--- a/tools/virtiofsd/passthrough_ll.c
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+++ b/tools/virtiofsd/passthrough_ll.c
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@@ -3001,7 +3001,7 @@ int main(int argc, char *argv[])
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     struct lo_data lo = {
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         .debug = 0,
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         .writeback = 0,
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-        .posix_lock = 1,
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+        .posix_lock = 0,
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         .proc_self_fd = -1,
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     };
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     struct lo_map_elem *root_elem;
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-- 
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2.27.0
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