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Bottomley" , Helge Deller , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Paul Walmsley , Palmer Dabbelt , Albert Ou , Thomas Gleixner , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , Josh Poimboeuf , Jiri Kosina , Miroslav Benes , Petr Mladek , Joe Lawrence , Colin Ian King , Masami Hiramatsu , Nicholas Piggin , Jisheng Zhang , linux-csky@vger.kernel.org, linux-kernel@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, live-patching@vger.kernel.org Subject: Re: [PATCH 2/2] ftrace: prevent preemption in perf_ftrace_function_call() Message-ID: References: <8c7de46d-9869-aa5e-2bb9-5dbc2eda395e@linux.alibaba.com> <7ec34e08-a357-58d6-2ce4-c7472d8b0381@linux.alibaba.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <7ec34e08-a357-58d6-2ce4-c7472d8b0381@linux.alibaba.com> X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org T24gVHVlLCBPY3QgMTIsIDIwMjEgYXQgMDE6NDA6MzFQTSArMDgwMCwg546L6LSHIHdyb3RlOgoK PiBkaWZmIC0tZ2l0IGEva2VybmVsL3RyYWNlL3RyYWNlX2V2ZW50X3BlcmYuYyBiL2tlcm5lbC90 cmFjZS90cmFjZV9ldmVudF9wZXJmLmMKPiBpbmRleCA2YWVkMTBlLi4zM2MyZjc2IDEwMDY0NAo+ IC0tLSBhL2tlcm5lbC90cmFjZS90cmFjZV9ldmVudF9wZXJmLmMKPiArKysgYi9rZXJuZWwvdHJh Y2UvdHJhY2VfZXZlbnRfcGVyZi5jCj4gQEAgLTQ0MSwxMiArNDQxLDE5IEBAIHZvaWQgcGVyZl90 cmFjZV9idWZfdXBkYXRlKHZvaWQgKnJlY29yZCwgdTE2IHR5cGUpCj4gIAlpZiAoIXJjdV9pc193 YXRjaGluZygpKQo+ICAJCXJldHVybjsKPiAKPiArCS8qCj4gKwkgKiBQcmV2ZW50IENQVSBjaGFu Z2luZyBmcm9tIG5vdyBvbi4gcmN1IG11c3QKPiArCSAqIGJlIGluIHdhdGNoaW5nIGlmIHRoZSB0 YXNrIHdhcyBtaWdyYXRlZCBhbmQKPiArCSAqIHNjaGVkdWxlZC4KPiArCSAqLwo+ICsJcHJlZW1w dF9kaXNhYmxlX25vdHJhY2UoKTsKPiArCj4gIAlpZiAoKHVuc2lnbmVkIGxvbmcpb3BzLT5wcml2 YXRlICE9IHNtcF9wcm9jZXNzb3JfaWQoKSkKPiAtCQlyZXR1cm47Cj4gKwkJZ290byBvdXQ7Cj4g Cj4gIAliaXQgPSBmdHJhY2VfdGVzdF9yZWN1cnNpb25fdHJ5bG9jayhpcCwgcGFyZW50X2lwKTsK PiAgCWlmIChiaXQgPCAwKQo+IC0JCXJldHVybjsKPiArCQlnb3RvIG91dDsKPiAKPiAgCWV2ZW50 ID0gY29udGFpbmVyX29mKG9wcywgc3RydWN0IHBlcmZfZXZlbnQsIGZ0cmFjZV9vcHMpOwo+IAoK VGhpcyBzZWVtcyByYXRoZXIgZGFmdCwgd291bGRuJ3QgaXQgYmUgZWFzaWVyIHRvIGp1c3QgcHV0 IHRoYXQgY2hlY2sKdW5kZXIgdGhlIHJlY3Vyc2lvbiB0aGluZz8KCl9fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmxpbnV4LXJpc2N2IG1haWxpbmcgbGlzdAps aW51eC1yaXNjdkBsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3Jn L21haWxtYW4vbGlzdGluZm8vbGludXgtcmlzY3YK