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[88.187.86.199]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-47a9e4d8410sm51612968f8f.15.2026.07.09.04.16.51 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 09 Jul 2026 04:16:54 -0700 (PDT) Message-ID: Date: Thu, 9 Jul 2026 13:16:51 +0200 Precedence: bulk X-Mailing-List: loongarch@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [patch 06/18] riscv/syscall: Use syscall_enter_from_user_mode_randomize_stack() Content-Language: en-US To: Thomas Gleixner , LKML Cc: Peter Zijlstra , Paul Walmsley , Palmer Dabbelt , linux-riscv@lists.infradead.org, Michael Ellerman , Shrikanth Hegde , linuxppc-dev@lists.ozlabs.org, Kees Cook , Huacai Chen , loongarch@lists.linux.dev, Sven Schnelle , linux-s390@vger.kernel.org, x86@kernel.org, Mark Rutland , Jinjie Ruan , Andy Lutomirski , Oleg Nesterov , Richard Henderson , Russell King , Catalin Marinas , Guo Ren , Geert Uytterhoeven , Thomas Bogendoerfer , Helge Deller , Yoshinori Sato , Richard Weinberger , Chris Zankel , linux-arm-kernel@lists.infradead.org, linux-alpha@vger.kernel.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-um@lists.infradead.org, Arnd Bergmann , Vineet Gupta , Will Deacon , Brian Cain , Michal Simek , Dinh Nguyen , "David S. Miller" , Andreas Larsson , linux-snps-arc@lists.infradead.org, linux-hexagon@vger.kernel.org, linux-openrisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, =?UTF-8?Q?Michal_Such=C3=A1nek?= , Jonathan Corbet , linux-doc@vger.kernel.org References: <20260707181957.433213175@kernel.org> <20260707190253.974626922@kernel.org> From: =?UTF-8?Q?Philippe_Mathieu-Daud=C3=A9?= In-Reply-To: <20260707190253.974626922@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Proofpoint-Spam-Info: AW1haW4tMjYwNzA5MDEwOCBTYWx0ZWRfX50/AKmd0PvLR ya94zoKZjOzA3xRpbxznOoh+HUIoZAZZx8f7iEHMH9Cwa63+oy5j8IBDp2JInE/lCfN77B8G+UP 5w4dQj/SlyUWlJ15y6oKHcZu8UVneMU= X-Proofpoint-ORIG-GUID: BY77HU8gqg4QKzIpvoRRkVMI2rOmpZ2b X-Authority-Analysis: v=2.4 cv=cOLQdFeN c=1 sm=1 tr=0 ts=6a4f8328 cx=c_pps a=JbAStetqSzwMeJznSMzCyw==:117 a=4s3hRJSeHn4rkQlkrse1kQ==:17 a=IkcTkHD0fZMA:10 a=RAioF0-LDSMA:10 a=M51BFTxLslgA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=_K5XuSEh1TEqbUxoQ0s3:22 a=VwQbUJbxAAAA:8 a=_O3DOGVWAAAA:8 a=JfrnYn6hAAAA:8 a=EUspDBNiAAAA:8 a=DoJJhcVa48uSEvU2-xUA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=uxP6HrT_eTzRwkO_Te1X:22 a=2TKV-7w1aU1AVAwN0oqT:22 a=1CNFftbPRP8L7MoqJWF3:22 X-Proofpoint-GUID: BY77HU8gqg4QKzIpvoRRkVMI2rOmpZ2b X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzA5MDEwOCBTYWx0ZWRfX2Mudb8JPbpa5 0pyJ+0MtbHHDBLHyrTXVwDNwBW+s/BY+YBxf6bqVHnhRehNTqWhiRKKeAIYgOgJe5whW3yDef8v wqMnxrJfntqBiUHeyx/oKIBJiNUofyW6gSJuMGZRtsr+eH4sNUB/FT2Y6C7aJuylaOP9/qfvKih 41mC3ubwb2pFRU4vebDh8dAzguBmkRlXUAy9ViUxsSmWJAL/UGdrMzQ2Xwf9D0lFSY8UJqp5uXr F96rMlfxoYKsmzDaYKXZR22DBy62cmTqes5cT7wjOWK/lUtpoqXuIH/kX3l3hfqaYOAaV/SW+DA 4mQYOozL9zKzAY2tQdRpkTETrUrAoetd70zhWOb/P1pYc4A97cdvhx5ZKNEwb2YDpnG4Ti4xFxT R44jVSnYIPhm1MYJPWF1oWw84u7M0Er1oJF77mVwkccfZ4xC7csDUtk1EUtW5kc76GzOq+j5H0u JzM0PBPmJabtsCRyJQg== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-07-09_02,2026-07-09_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 clxscore=1011 priorityscore=1501 bulkscore=0 spamscore=0 lowpriorityscore=0 phishscore=0 suspectscore=0 impostorscore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2607090108 On 7/7/26 21:06, Thomas Gleixner wrote: > syscall_enter_from_user_mode_randomize_stack() replaces > syscall_enter_from_user_mode() and the subsequent invocation of > add_random_kstack_offset(). > > The advantage is that it applies the stack randomization right after > enter_from_user_mode() and thereby avoids the overhead of get/put_cpu_var() > as that code is invoked with interrupts disabled. > > No functional change. > > Signed-off-by: Thomas Gleixner > Cc: Paul Walmsley > Cc: Palmer Dabbelt > Cc: linux-riscv@lists.infradead.org > --- > arch/riscv/kernel/traps.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) Reviewed-by: Philippe Mathieu-Daudé