Deciphering the hard-coded list of integer return values from
nbd_start_negotiate() will only get more confusing when adding support
for 64-bit extended headers. Better is to name things in an enum.
Although the function in question is private to client.c, putting the
enum in a public header and including an enum-to-string conversion
will allow its use in more places in upcoming patches.
The enum is intentionally laid out so that operators like <= can be
used to group multiple modes with similar characteristics, and where
the least powerful mode has value 0, even though this patch does not
exploit that. No semantic change intended.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230608135653.2918540-9-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Our existing use of structured replies either reads into a qiov capped
at 32M (NBD_CMD_READ) or caps allocation to 1000 bytes (see
NBD_MAX_MALLOC_PAYLOAD in block/nbd.c). But the existing length
checks are rather late; if we encounter a buggy (or malicious) server
that sends a super-large payload length, we should drop the connection
right then rather than assuming the layer on top will be careful.
This becomes more important when we permit 64-bit lengths which are
even more likely to have the potential for attempted denial of service
abuse.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20230608135653.2918540-8-eblake@redhat.com>
Our code relies on a sentinel cookie value of zero for deciding when a
packet has been handled, as well as relying on array indices between 0
and MAX_NBD_REQUESTS-1 for dereferencing purposes. As long as we can
symmetrically convert between two forms, there is no reason to go with
the odd choice of using XOR with a random pointer, when we can instead
simplify the mappings with a mere offset of 1.
Using ((uint64_t)-1) as the sentinel instead of NULL such that the two
macros could be entirely eliminated might also be possible, but would
require a more careful audit to find places where we currently rely on
zero-initialization to be interpreted as the sentinel value, so I did
not pursue that course.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230608135653.2918540-7-eblake@redhat.com>
[eblake: enhance commit message]
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Externally, libnbd exposed the 64-bit opaque marker for each client
NBD packet as the "cookie", because it was less confusing when
contrasted with 'struct nbd_handle *' holding all libnbd state. It
also avoids confusion between the noun 'handle' as a way to identify a
packet and the verb 'handle' for reacting to things like signals.
Upstream NBD changed their spec to favor the name "cookie" based on
libnbd's recommendations[1], so we can do likewise.
[1] https://github.com/NetworkBlockDevice/nbd/commit/ca4392eb2b
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230608135653.2918540-6-eblake@redhat.com>
[eblake: typo fix]
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Part of NBD's 64-bit headers extension involves passing the client's
requested offset back as part of the reply header (one reason it
stated for this change: converting absolute offsets stored in
NBD_REPLY_TYPE_OFFSET_DATA to relative offsets within the buffer is
easier if the absolute offset of the buffer is also available). This
is a refactoring patch to pass the full request around the reply
stack, rather than just the handle, so that later patches can then
access request->from when extended headers are active. Meanwhile,
this patch enables us to now assert that simple replies are only
attempted when appropriate, and otherwise has no semantic change.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20230608135653.2918540-5-eblake@redhat.com>
Upstream NBD now documents[1] an extension that supports 64-bit effect
lengths in requests. As part of that extension, the size of the reply
headers will change in order to permit a 64-bit length in the reply
for symmetry[2]. Additionally, where the reply header is currently 16
bytes for simple reply, and 20 bytes for structured reply; with the
extension enabled, there will only be one extended reply header, of 32
bytes, with both structured and extended modes sending identical
payloads for chunked replies.
Since we are already wired up to use iovecs, it is easiest to allow
for this change in header size by splitting each structured reply
across multiple iovecs, one for the header (which will become wider in
a future patch according to client negotiation), and the other(s) for
the chunk payload, and removing the header from the payload struct
definitions. Rename the affected functions with s/structured/chunk/
to make it obvious that the code will be reused in extended mode.
Interestingly, the client side code never utilized the packed types,
so only the server code needs to be updated.
[1] https://github.com/NetworkBlockDevice/nbd/blob/extension-ext-header/doc/proto.md
as of NBD commit e6f3b94a934
[2] Note that on the surface, this is because some future server might
permit a 4G+ NBD_CMD_READ and need to reply with that much data in one
transaction. But even though the extended reply length is widened to
64 bits, for now the NBD spec is clear that servers will not reply
with more than a maximum payload bounded by the 32-bit
NBD_INFO_BLOCK_SIZE field; allowing a client and server to mutually
agree to transactions larger than 4G would require yet another
extension.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230608135653.2918540-4-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
We had a mix of struct declarations followed by typedefs, and direct
struct definitions as part of a typedef. Pick a single style. Also
float forward declarations of opaque types to the top of the file,
rather than interspersed with function declarations, which will help a
future patch that wants to expose yet another opaque type that will be
referenced in NBDRequest. No semantic impact.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230608135653.2918540-3-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
[eblake: alter patch per mailing list feedback]
Signed-off-by: Eric Blake <eblake@redhat.com>
Assigning strlen() to a uint32_t and then asserting that it isn't too
large doesn't catch the case of an input string 4G in length.
Thankfully, the incoming strings can never be that large: if the
export name or query is reflecting a string the client got from the
server, we already guarantee that we dropped the NBD connection if the
server sent more than 32M in a single reply to our NBD_OPT_* request;
if the export name is coming from qemu, nbd_receive_negotiate()
asserted that strlen(info->name) <= NBD_MAX_STRING_SIZE; and
similarly, a query string via x->dirty_bitmap coming from the user was
bounds-checked in either qemu-nbd or by the limitations of QMP.
Still, it doesn't hurt to be more explicit in how we write our
assertions to not have to analyze whether inadvertent wraparound is
possible.
Fixes: 93676c88 ("nbd: Don't send oversize strings", v4.2.0)
Reported-by: Dr. David Alan Gilbert <dave@treblig.org>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20230608135653.2918540-2-eblake@redhat.com>
Pass 'verbose' to nbd_client_thread() inside NbdClientOpts which looks
a little bit cleaner and make it bool as it is used as bool actually.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20230717202520.236999-1-den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Fail on error, we are in trouble.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20230717145544.194786-6-den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: avoid intermediate variable]
Signed-off-by: Eric Blake <eblake@redhat.com>
We are trying to temporarily redirect stderr of daemonized process to
a pipe to report a error and get failed. In that case we could not
use error_report() helper, but should write the message directly into
the problematic pipe.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20230717145544.194786-4-den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: rearrange patch series, fix typo]
Signed-off-by: Eric Blake <eblake@redhat.com>
errno has been overwritten by dup2() just below qemu_daemon() and thus
improperly returned to the caller. Fix accordingly.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20230717145544.194786-5-den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: reorder patch series]
Signed-off-by: Eric Blake <eblake@redhat.com>
Commit e6df58a557
Author: Hanna Reitz <hreitz@redhat.com>
Date: Wed May 8 23:18:18 2019 +0200
qemu-nbd: Do not close stderr
has introduced an interesting regression. Original behavior of
ssh somehost qemu-nbd /home/den/tmp/file -f raw --fork
was the following:
* qemu-nbd was started as a daemon
* the command execution is done and ssh exited with success
The patch has changed this behavior and 'ssh' command now hangs forever.
According to the normal specification of the daemon() call, we should
endup with STDERR pointing to /dev/null. That should be done at the
very end of the successful startup sequence when the pipe to the
bootstrap process (used for diagnostics) is no longer needed.
This could be achived in the same way as done for 'qemu-nbd -c' case.
That was commit 0eaf453e, also fixing up e6df58a5. STDOUT copying to
STDERR does the trick.
This also leads to proper 'ssh' connection closing which fixes my
original problem.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
CC: Hanna Reitz <hreitz@redhat.com>
CC: <qemu-stable@nongnu.org>
Message-ID: <20230717145544.194786-3-den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
We are going to pass additional flag inside next patch.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
CC: <qemu-stable@nongnu.org>
Message-ID: <20230717145544.194786-2-den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
* Fix LMUL check to use VLEN
* Fix typo field in NUMA error_report
* check priv_ver before auto-enable zca/zcd/zcf
* Fix disas output of upper immediates
* tidy CPU firmware section
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Merge tag 'pull-riscv-to-apply-20230719-1' of https://github.com/alistair23/qemu into staging
Fourth RISC-V PR for 8.1
* Fix LMUL check to use VLEN
* Fix typo field in NUMA error_report
* check priv_ver before auto-enable zca/zcd/zcf
* Fix disas output of upper immediates
* tidy CPU firmware section
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# gpg: Signature made Wed 19 Jul 2023 05:44:51 BST
# gpg: using RSA key 6AE902B6A7CA877D6D659296AF7C95130C538013
# gpg: Good signature from "Alistair Francis <alistair@alistair23.me>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 6AE9 02B6 A7CA 877D 6D65 9296 AF7C 9513 0C53 8013
* tag 'pull-riscv-to-apply-20230719-1' of https://github.com/alistair23/qemu:
target/riscv: Fix LMUL check to use VLEN
hw/riscv: Fix typo field in error_report
target/riscv/cpu.c: check priv_ver before auto-enable zca/zcd/zcf
riscv/disas: Fix disas output of upper immediates
docs/system/target-riscv.rst: tidy CPU firmware section
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In commit 2fda0726e5 ("hw/nvme: fix missing endian conversions for
doorbell buffers"), we fixed shadow doorbells for big-endian guests
running on little endian hosts. But I did not fix little-endian guests
on big-endian hosts. Fix this.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1765
Fixes: 3f7fe8de3d ("hw/nvme: Implement shadow doorbell buffer support")
Cc: qemu-stable@nongnu.org
Reported-by: Thomas Huth <thuth@redhat.com>
Tested-by: Cédric Le Goater <clg@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
The previous check was failing with:
VLEN=128 ELEN = 64 SEW = 16 and LMUL = 1/8 which is a
valid combination.
Fix the check to allow valid combinations when VLEN is a multiple of
ELEN.
From the specification:
"In general, the requirement is to support LMUL ≥ SEWMIN/ELEN, where
SEWMIN is the narrowest supported SEW value and ELEN is the widest
supported SEW value. In the standard extensions, SEWMIN=8. For standard
vector extensions with ELEN=32, fractional LMULs of 1/2 and 1/4 must be
supported. For standard vector extensions with ELEN=64, fractional LMULs
of 1/2, 1/4, and 1/8 must be supported." Elsewhere in the specification
it makes clear that VLEN>=ELEN.
From inspection this new check allows:
VLEN=ELEN=64 1/2, 1/4, 1/8 for SEW >=8
VLEN=ELEN=32 1/2, 1/4 for SEW >=8
Fixes: d9b7609a1f ("target/riscv: rvv-1.0: configure instructions")
Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Message-Id: <20230718131316.12283-2-rbradford@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
"smp.cpus" means the number of online CPUs and "smp.max_cpus" means the
total number of CPUs.
riscv_numa_get_default_cpu_node_id() checks "smp.cpus" and the
"available CPUs" description in the next error message also indicates
online CPUs.
So report "smp.cpus" in error_report() instand of "smp.max_cpus".
Since "smp.cpus" is "unsigned int", use "%u".
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230718080712.503333-1-zhao1.liu@linux.intel.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Commit bd30559568 made changes in how we're checking and disabling
extensions based on env->priv_ver. One of the changes was to move the
extension disablement code to the end of realize(), being able to
disable extensions after we've auto-enabled some of them.
An unfortunate side effect of this change started to happen with CPUs
that has an older priv version, like sifive-u54. Starting on commit
2288a5ce43 we're auto-enabling zca, zcd and zcf if RVC is enabled,
but these extensions are priv version 1.12.0. When running a cpu that
has an older priv ver (like sifive-u54) the user is spammed with
warnings like these:
qemu-system-riscv64: warning: disabling zca extension for hart 0x0000000000000000 because privilege spec version does not match
qemu-system-riscv64: warning: disabling zcd extension for hart 0x0000000000000000 because privilege spec version does not match
The warnings are part of the code that disables the extension, but in this
case we're throwing user warnings for stuff that we enabled on our own,
without user intervention. Users are left wondering what they did wrong.
A quick 8.1 fix for this nuisance is to check the CPU priv spec before
auto-enabling zca/zcd/zcf. A more appropriate fix will include a more
robust framework that will account for both priv_ver and user choice
when auto-enabling/disabling extensions, but for 8.1 we'll make it do
with this simple check.
It's also worth noticing that this is the only case where we're
auto-enabling extensions based on a criteria (in this case RVC) that
doesn't match the priv spec of the extensions we're enabling. There's no
need for more 8.1 band-aids.
Cc: Conor Dooley <conor@kernel.org>
Fixes: 2288a5ce43 ("target/riscv: add cfg properties for Zc* extension")
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Message-Id: <20230717154141.60898-1-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The GNU assembler produces the following output for instructions
with upper immediates:
00002597 auipc a1,0x2
000024b7 lui s1,0x2
6409 lui s0,0x2 # c.lui
The immediate operands of upper immediates are not shifted.
However, the QEMU disassembler prints them shifted:
00002597 auipc a1,8192
000024b7 lui s1,8192
6409 lui s0,8192 # c.lui
The current implementation extracts the immediate bits and shifts the by 12,
so the internal representation of the immediate is the actual immediate.
However, the immediates are later printed using rv_fmt_rd_imm or
rv_fmt_rd_offset, which don't undo the shift.
Let's fix this by using specific output formats for instructions
with upper immediates, that take care of the shift.
Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230711075051.1531007-1-christoph.muellner@vrull.eu>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This is how the content of the "RISC-V CPU firmware" section is
displayed after the html is generated:
"When using the sifive_u or virt machine there are three different
firmware boot options: 1. -bios default - This is the default behaviour
if no -bios option is included. (...) 3. -bios <file> - Tells QEMU to
load the specified file as the firmware."
It's all in the same paragraph, in a numbered list, and no special
formatting for the options.
Tidy it a bit by adding line breaks between items and its description.
Remove the numbered list. And apply formatting for the options cited in
the middle of the text.
Cc: qemu-trivial@nongnu.org
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20230712143728.383528-1-dbarboza@ventanamicro.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
qemu-user crashes immediately when running static binaries on the armhf
architecture. The problem is the memory layout where the executable is
loaded before the interpreter library, in which case the reserved brk
region clashes with the interpreter code and is released before qemu
tries to start the program.
At load time qemu calculates a brk value for interpreter and executable
each. The fix is to choose the higher one of both.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Andreas Schwab <schwab@suse.de>
Cc: qemu-stable@nongnu.org
Reported-by: Venkata.Pyla@toshiba-tsip.com
Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1040981
The old_mmap syscall (e.g. on i386) hands over the parameters in
a struct. Adjust the strace output to print the correct values.
Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: John Reiser <jreiser@BitWagon.com>
Closes: https://gitlab.com/qemu-project/qemu/-/issues/1760
Fix the math overflow when calculating the new_malloc_size.
new_host_brk_page and brk_page are unsigned integers. If userspace
reduces the heap, new_host_brk_page is lower than brk_page which results
in a huge positive number (but should actually be negative).
Fix it by adding a proper check and as such make the code more readable.
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
Since commit 86f04735ac ("linux-user: Fix brk() to release pages") it's
possible for userspace applications to reduce their memory footprint by
calling brk() with a lower address and free up memory. Before that commit
guest heap memory was never unmapped.
But the Linux kernel prohibits to reduce brk() below the initial memory
address which is set at startup by the set_brk() function in binfmt_elf.c.
Such a range check was missed in commit 86f04735ac.
This patch adds the missing check by storing the initial brk value in
initial_target_brk and verify any new brk addresses against that value.
Tested with the i386 upx binary from
https://github.com/upx/upx/releases/download/v4.0.2/upx-4.0.2-i386_linux.tar.xz
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
The qemu brk() implementation is too aggressive and cleans remaining bytes
on the current page above the last brk address.
But some existing applications are buggy and read/write bytes above their
current heap address. On a phyiscal machine this does not trigger a
runtime error as long as the access happens on the same page. Additionally
the Linux kernel allocates only full pages and does no zeroing on already
allocated pages, even if the brk address is lowered.
Fix qemu to behave the same way as the kernel does. Do not touch already
allocated pages, and - when running with different page sizes of guest and
host - zero out only those memory areas where the host page size is bigger
than the guest page size.
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
The test fails occasionally, see e.g.:
https://gitlab.com/thuth/qemu/-/jobs/4196177756#L489https://gitlab.com/thuth/qemu/-/jobs/4623296271#L290
It also fails on my laptop in ca. 50% of all runs. Thus disable it by
default by using the QEMU_TEST_FLAKY_TESTS environment variable to fence
it (which we also already use in flaky qtests). While we're at it, also
document this variable in docs/devel/testing.rst.
Message-Id: <20230710170155.7192-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Get an up-to-date package list from lcitool, that way we
don't need to manually keep this array in sync.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Inspired-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230711144922.67491-5-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Add the get_qemu_packages_from_lcitool_json() helper which return
such package list from a lcitool env var file in JSON format.
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230711144922.67491-4-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Refresh the generated files by running:
$ make lcitool-refresh
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230711144922.67491-3-philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
[thuth: Drop changes to libpmem-dev and libxen-dev]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Add the generate_pkglist() helper to generate a list of packages
required by a distribution to build QEMU.
Since we can not add a "THIS FILE WAS AUTO-GENERATED" comment in
JSON, create the files under tests/vm/generated/ sub-directory;
add a README mentioning the files are generated.
Suggested-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20230711144922.67491-2-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
This wasn't noticed because the test is currently disabled.
Fixes: 02f56e3de ("tests/qtest: massively speed up migration-test")
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Message-Id: <20230711212131.2370-1-farosas@suse.de>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
elf_hwcap_str() takes a bit number, but compares it for equality with
the HWCAP_S390_* masks. This causes /proc/cpuinfo to display incorrect
hwcaps.
Fix by introducing the HWCAP_S390_NR_* constants and using them in
elf_hwcap_str() instead of the HWCAP_S390_*. While at it, add the
missing nnpa, pcimio and sie hwcaps from the latest kernel.
Output before:
features : esan3 zarch stfle msa
Output after:
features : esan3 zarch stfle msa ldisp eimm etf3eh highgprs vx vxe
Fixes: e19807bee3 ("linux-user/elfload: Introduce elf_hwcap_str() on s390x")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230627151356.273259-1-iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
If QEMU is built with --without-default-devices, the s390-flic-kvm
device is missing and QEMU aborts when started with the KVM accelerator.
Make sure it's available by selecting S390_FLIC_KVM in Kconfig.
Consequently, this also fixes an abort in tests/qtest/migration-test.
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Message-Id: <20230711151440.716822-1-clg@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
blk_io_plug_call() is invoked outside a blk_io_plug()/blk_io_unplug()
section while opening the NVMe drive from:
nvme_file_open() ->
nvme_init() ->
nvme_identify() ->
nvme_admin_cmd_sync() ->
nvme_submit_command() ->
blk_io_plug_call()
blk_io_plug_call() immediately invokes the given callback when the
current thread is not plugged, as is the case during nvme_file_open().
Unfortunately, nvme_submit_command() calls blk_io_plug_call() with
q->lock still held:
...
q->sq.tail = (q->sq.tail + 1) % NVME_QUEUE_SIZE;
q->need_kick++;
blk_io_plug_call(nvme_unplug_fn, q);
qemu_mutex_unlock(&q->lock);
^^^^^^^^^^^^^^^^^^^^^^^^^^^
nvme_unplug_fn() deadlocks trying to acquire q->lock because the lock is
already acquired by the same thread. The symptom is that QEMU hangs
during startup while opening the NVMe drive.
Fix this by moving the blk_io_plug_call() outside q->lock. This is safe
because no other thread runs code related to this queue and
blk_io_plug_call()'s internal state is immune to thread safety issues
since it is thread-local.
Reported-by: Lukáš Doktor <ldoktor@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Lukas Doktor <ldoktor@redhat.com>
Message-id: 20230712191628.252806-1-stefanha@redhat.com
Fixes: f2e590002b ("block/nvme: convert to blk_io_plug_call() API")
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Follow PulseAudio backend comment and code, and only implement the
channels QEMU actually supports at this point, and add the same comment
about limits and future mappings. Simplify a bit the code.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20230506163735.3481387-13-marcandre.lureau@redhat.com>
