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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250526162940.GB4156@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 5BE3940002 X-Stat-Signature: 43abshrjx8brxpdpru4poyqzkntboqib X-Rspam-User: X-HE-Tag: 1748281187-733112 X-HE-Meta: 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 oAroXqHz SIHpJtW3fi2DZWUYPlAUnvRuaos4ScNJnJ//z6vV8kRNQEe0QTNKEx1mBNQcIvSuyp2LCoWWfCZBBHThVx9XbDZa5vlOCS2YM4pq5oUI9qT31IHK+TdkJJqAYut1RoEGtR8omi4zJpUQN7oX/BPRrMzbPmP9jn/uwp/V/6KJ/TPseAOcrMQ3hY3b5IpQ52CeGmD4DFR+7i5/NCgQBiT+ZBwsHFBH0in87PR0DNAJpOaNkLlBNhVORo49Noa+0/Hpv2phKqJVczAgjRnlYjU44M+5TMueZBpq9BzIskVzVfEI6HBrq8rBwScGsuBg4iEcPvT6O X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 05/26, Oleg Nesterov wrote: > > On 05/25, David Hildenbrand wrote: > > > > On 25.05.25 11:59, Oleg Nesterov wrote: > > > > > >OK. But do you see any reason why uprobe_mmap() should be ever called during > > >mremap() ? > > > > Only when growing a VMA: we might now cover a part with a uprobe, which we > > have take care of. > > Ah, indeed, thank you... > > But. What if mremap() expands and moves a VMA? it seems to me that in > this case uprobe_mmap() won't be called? I'll try to make the test-case > to check... It seems that I was right... #define _GNU_SOURCE #include #include #include #include #include #include #define FNAME "FILE" #define ADDR (4096*16) int main(int argc, char *argv[]) { int fd = open(FNAME, O_RDWR|O_CREAT, 0600); ftruncate(fd, 2*4096); struct perf_event_attr attr = { .type = 9, .size = 72, // PERF_ATTR_SIZE_VER1 to include config2 .config1 = (long)FNAME, // uprobe_path .config2 = 4096, // probe_offset }; assert(syscall(__NR_perf_event_open, &attr, 0, 0, -1, 0) >= 0); assert(mmap((void*)ADDR, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED, fd,0) == (void*)ADDR); int flags = 0; flags = MREMAP_MAYMOVE|MREMAP_FIXED; assert(mremap((void*)ADDR, 4096, 2*4096, flags, 2*ADDR) == (void*)(2*ADDR)); pause(); return 0; } and /tmp/D# ./test & [1] 102 /tmp/D# grep FILE /proc/$!/maps 00020000-00022000 r-xp 00000000 00:15 2060 /tmp/D/FILE this test-case doesn't call uprobe_mmap/install_breakpoint during mremap(). I added a couple of printk's to ensure. If I remove the flags = MREMAP_MAYMOVE|MREMAP_FIXED; line above, everything works "as expected". Oleg.