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envelope-from=iii@linux.ibm.com; helo=mx0b-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Hi, This is an attempt to improve the vma-pthread test situation sparked by a bug report by wasmtime project. The patch doesn't fix all issues, but it definitely makes things better and I think I understand what particular thread interleaving leads to the issue (details are in the commit message). There is at least one other thing that I find suspicious about the current code: page_check_range() fetches itree.last twice, and indeed, using qatomic_read() there makes things even better, but still not perfect, and I still cannot clearly elaborate what is the exact interleaving with pageflags_set_clear() that causes a problem there, so I'm not sending that one for now. Best regards, Ilya Ilya Leoshkevich (1): accel/tcg: Retry page_check_range() on itree.start inconsistency accel/tcg/user-exec.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) -- 2.54.0