[GIT PULL] register: avoid overshooting the file descriptor limit

[vpfkfl753]

File registration adds the requested table size to the current soft limit. With soft=64, hard=96 and a request for 80 files, the resulting limit of 144 is rejected and registration returns -EMFILE, even though 80 is allowed.

Set the soft limit to the requested size. The regression covers regular, tagged and sparse tables in separate child processes and checks that the hard limit is unchanged.

The new test fails in all three modes before the fix. Afterward, it and file-register, file-update, file-verify, file-exit-unreg, and io_uring_register pass on Linux 7.0.0-28-generic with GCC 13.3.

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git request-pull output:

The following changes since commit 4cf73437863c2e492d2a1d0f24330f391c0f075b:

  test/iowait.t: Skip if system is not quiesced for too long (2026-08-31 17:00:18 -0600)

are available in the Git repository at:

  https://github.com/vpfkfl753/liburing.git fix-register-nofile-limit

for you to fetch changes up to 5730376586eb6bade05116a59f5e255c132bda04:

  register: avoid overshooting the file descriptor limit (2026-09-08 21:21:03 +0900)

----------------------------------------------------------------
Sungwon Woo (1):
      register: avoid overshooting the file descriptor limit

 src/register.c              |  2 +-
 test/Makefile               |  1 +
 test/file-register-nofile.c | 94 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 96 insertions(+), 1 deletion(-)
 create mode 100644 test/file-register-nofile.c

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src/queue: don't flush SQ ring for new wait interface

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Fixes: https://github.com/axboe/liburing/issues/402
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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