From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: race condition between shutdown() and post_reset() resulting in deadlock From: Oliver Neukum Message-Id: <1516096667.7049.8.camel@suse.com> Date: Tue, 16 Jan 2018 10:57:47 +0100 To: Hans de Goede Cc: linux-usb@vger.kernel.org List-ID: SGksCgpsb29raW5nIGF0IHlvdXIgbGFzdCBwYXRjaCBJIG5vdGljZWQgc29tZXRoaW5nLgpJIHRo aW5rIGl0IGZhaWxzIHRvIHdvcmsgaWYgd2UgaGl0IGEgcGVjdWxpYXIgcmFjZSBjb25kaXRpb24u Ckl0IGxvb2tzIHRvIG1lIGxpa2Ugd2UgY2FuIGdldCB0aGUgZm9sbG93aW5nOgoKdGFzayBBCgpw cmVfcmVzZXQoKQrCoCAtLT4gY2FsbGluZyBzY3NpX2Jsb2NrX3JlcXVlc3RzKCkKCgkJCQkJdGFz ayBCCgoJCQkJCXNodXRkb3duKCkKCQkJCQnCoCAtLT4gc2V0dGluZyB0aGUgc2h1dGRvd24gZmxh ZwoKCnBvc3RfcmVzZXQoKQrCoCAtLT4gY2hlY2tpbmcgdGhlIGZsYWcgLT4gZG8gbm90aGluZyAt PiBkZWFkbG9jawoKU28gd2UgbmVlZCBpbiBhZGRpdGlvbiBzb21ldGhpbmcgbGlrZSB0aGUgYmVs b3cgcGF0Y2guCldoYXQgZG8geW91IHRoaW5rPwoKCVJlZ2FyZHMKCQlPbGl2ZXIKCkZyb20gNjhj Yzg5NDBkN2RkZThlMmE0ODIxN2Q4MDg2Y2Q2OTI4MDllNzk4MCBNb24gU2VwIDE3IDAwOjAwOjAw IDIwMDEKRnJvbTogT2xpdmVyIE5ldWt1bSA8b25ldWt1bUBzdXNlLmNvbT4KRGF0ZTogTW9uLCAx NSBKYW4gMjAxOCAxMzo1Njo1OSArMDEwMApTdWJqZWN0OiBbUEFUQ0hdIFVBUzogZml4IHJhY2Ug YmV0d2VlbiBwb3N0X3Jlc2V0KCkgYW5kIHNodXRkb3duKCkKCkRpc2Nvbm5lY3QgZHVlIHRvIHNo dXRkb3duIGNhbiBoYXBwZW4gYWZ0ZXIgcHJlX3Jlc2V0KCkgaGFzIGJlZW4gY2FsbGVkLiBUaHVz IHRoZSBob3N0Cm11c3QgYmUgdW5ibG9ja2VkIGV2ZW4gaW4gdGhlIHNodXRkb3duIGNhc2UuCgpT aWduZWQtb2ZmLWJ5OiBPbGl2ZXIgTmV1a3VtIDxvbmV1a3VtQHN1c2UuY29tPgotLS0KIGRyaXZl cnMvdXNiL3N0b3JhZ2UvdWFzLmMgfCA2ICsrKystLQogMSBmaWxlIGNoYW5nZWQsIDQgaW5zZXJ0 aW9ucygrKSwgMiBkZWxldGlvbnMoLSkKCmRpZmYgLS1naXQgYS9kcml2ZXJzL3VzYi9zdG9yYWdl L3Vhcy5jIGIvZHJpdmVycy91c2Ivc3RvcmFnZS91YXMuYwppbmRleCAzMzgxMzNhMjM5ZGYuLmQ1 ZWQxZTU4MWZiNSAxMDA2NDQKLS0tIGEvZHJpdmVycy91c2Ivc3RvcmFnZS91YXMuYworKysgYi9k cml2ZXJzL3VzYi9zdG9yYWdlL3Vhcy5jCkBAIC0xMDQ2LDEwICsxMDQ2LDExIEBAIHN0YXRpYyBp bnQgdWFzX3Bvc3RfcmVzZXQoc3RydWN0IHVzYl9pbnRlcmZhY2UgKmludGYpCiAJc3RydWN0IFNj c2lfSG9zdCAqc2hvc3QgPSB1c2JfZ2V0X2ludGZkYXRhKGludGYpOwogCXN0cnVjdCB1YXNfZGV2 X2luZm8gKmRldmluZm8gPSAoc3RydWN0IHVhc19kZXZfaW5mbyAqKXNob3N0LT5ob3N0ZGF0YTsK IAl1bnNpZ25lZCBsb25nIGZsYWdzOwotCWludCBlcnI7CisJaW50IGVyciA9IDE7CiAKKwkvKiBX ZSBtYXkgaGF2ZSBsb3N0IHRoZSByYWNlIGFuZCBzaHV0ZG93biBhZnRlciBwcmVfcmVzZXQoKSAq LwogCWlmIChkZXZpbmZvLT5zaHV0ZG93bikKLQkJcmV0dXJuIDA7CisJCWdvdG8gc2tpcDsKIAog CWVyciA9IHVhc19jb25maWd1cmVfZW5kcG9pbnRzKGRldmluZm8pOwogCWlmIChlcnIgJiYgZXJy ICE9IEVOT0RFVikKQEAgLTEwNjIsNiArMTA2Myw3IEBAIHN0YXRpYyBpbnQgdWFzX3Bvc3RfcmVz ZXQoc3RydWN0IHVzYl9pbnRlcmZhY2UgKmludGYpCiAJc2NzaV9yZXBvcnRfYnVzX3Jlc2V0KHNo b3N0LCAwKTsKIAlzcGluX3VubG9ja19pcnFyZXN0b3JlKHNob3N0LT5ob3N0X2xvY2ssIGZsYWdz KTsKIAorc2tpcDoKIAlzY3NpX3VuYmxvY2tfcmVxdWVzdHMoc2hvc3QpOwogCiAJcmV0dXJuIGVy ciA/IDEgOiAwOwo=