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bh=Aa5HdpSOMwvBE7BMf+XvrXPD4qXbTjZMnG5Xm35eNe4=; b=lO8QQ/8JlaWqjE4nyyG0AAUnyPfA9TWqi5SCDy5UJ3D88Zj3g2k4OvZJc9hG33+lRB9YU0 6VzFa1tkTCvY3lFCi3sFGaJ5QcJQoqYkmwbsDJMDmRBKHbFHzUL6ZMrcUJ/FWGV8B8eb6R TQ8dGLIx8l+qqlAtXiIl90zjXFasfsM= X-Rspamd-Queue-Id: B5DDD40065 X-Rspam-User: Authentication-Results: imf17.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=QoVeUa7N; dmarc=pass (policy=none) header.from=intel.com; spf=pass (imf17.hostedemail.com: domain of shaoqin.huang@intel.com designates 134.134.136.100 as permitted sender) smtp.mailfrom=shaoqin.huang@intel.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}") X-Rspamd-Server: rspam10 X-Stat-Signature: 5gywnqiyiqptso7ithrw1bezb6jyrwph X-HE-Tag: 1662423870-383423 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: On 9/6/2022 2:50 AM, Edgecombe, Rick P wrote: > On Sat, 2022-09-03 at 10:13 +0800, Huang, Shaoqin wrote: >>> + BUG_ON(is_zero_pfn(pfn) && rw); >>> + >> >> Why we need use BUG_ON() here? Based on [1], we should avoid to use >> the >> BUG_ON() due to it will panic the machine. >> >> [1]: >> https://lore.kernel.org/lkml/20220824163100.224449-1-david@redhat.com/ > > Yea, you are probably right. All the rest of this checker uses BUG_ON() > though. Maybe they should all be something else? Just felt weird to > have this be the only check that is different. > > I don't have any objections to changing it to WARN_ON(). Should I > switch the rest of the checks here while I'm at it? Yes. I think in most situation, WARN_ON() or WARN_ON_ONCE() is ok.