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That's all we know. X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexander Bulekov , Richard Henderson , =?UTF-8?q?Alex=20Benn=C3=A9e?= , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" There is no particular reason why you can't have a watchpoint in TCG that covers a large chunk of the address space. We could be clever about it but these cases are pretty rare and we can assume the user will expect a little performance degradation. NB: In my testing gdb will silently squash a watchpoint like: watch (char[0x7fffffffff]) *0x0 to a 4 byte watchpoint. Practically it will limit the maximum size based on max-value-size. However given enough of a tweak the sky is the limit. Reported-by: Alexander Bulekov Signed-off-by: Alex Bennée --- v2 - use cleaner in_page = -(addr | TARGET_PAGE_MASK) logic per rth --- exec.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/exec.c b/exec.c index 5162f0d12f9..65a4376df37 100644 --- a/exec.c +++ b/exec.c @@ -1036,6 +1036,7 @@ int cpu_watchpoint_insert(CPUState *cpu, vaddr addr, vaddr len, int flags, CPUWatchpoint **watchpoint) { CPUWatchpoint *wp; + vaddr in_page; /* forbid ranges which are empty or run off the end of the address space */ if (len == 0 || (addr + len - 1) < addr) { @@ -1056,7 +1057,12 @@ int cpu_watchpoint_insert(CPUState *cpu, vaddr addr, vaddr len, QTAILQ_INSERT_TAIL(&cpu->watchpoints, wp, entry); } - tlb_flush_page(cpu, addr); + in_page = -(addr | TARGET_PAGE_MASK); + if (len <= in_page) { + tlb_flush_page(cpu, addr); + } else { + tlb_flush(cpu); + } if (watchpoint) *watchpoint = wp; -- 2.20.1