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Fri, 13 Nov 2026 09:06:38 -0800 (PST) X-Received: by 2002:a17:90a:dfcf:b0:3ac:7556:8eda with SMTP id 98e67ed59e1d1-3b1b0a1b56fmr2668105a91.26.1794589597671; Fri, 13 Nov 2026 09:06:37 -0800 (PST) Received: from [192.168.1.102] ([117.245.168.128]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3b1b3b110c0sm2247977a91.3.2026.11.13.09.06.31 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 13 Nov 2026 09:06:37 -0800 (PST) Message-ID: <2bae83be-bb44-4541-bf1c-5861f73a7394@redhat.com> Date: Fri, 13 Nov 2026 22:36:30 +0530 X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 1/5] kho: reject zero bootmem scale To: "Mike Rapoport (Microsoft)" , Jonathan Corbet , Pasha Tatashin , Pratyush Yadav Cc: Alexander Graf , Andrew Morton , Chen Pei , George Guo , Kexin Liu , Randy Dunlap , Shuah Khan , Sourabh Jain , kexec@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20261112-kho-bootmem-sizing-v3-0-f0c8d00295d5@kernel.org> <20261112-kho-bootmem-sizing-v3-1-f0c8d00295d5@kernel.org> Content-Language: en-US From: Mukesh Pilaniya In-Reply-To: <20261112-kho-bootmem-sizing-v3-1-f0c8d00295d5@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 12/11/26 4:08 pm, Mike Rapoport (Microsoft) wrote: > kho_bootmem=0% sets bootmem_scale to 0, and then the bootmem areas are > sized using the explicit sizes that default to 0. KHO remains enabled, > but there is no usable bootmem to load the next kernel. > > Reject zero scale the same way zero explicit sizes are rejected. > > Fixes: 3dc92c311498 ("kexec: add Kexec HandOver (KHO) generation helpers") > Signed-off-by: Mike Rapoport (Microsoft) > --- > kernel/liveupdate/kexec_handover.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > > diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_handover.c > index 6f1f55fe31819..b30ba686cb301 100644 > --- a/kernel/liveupdate/kexec_handover.c > +++ b/kernel/liveupdate/kexec_handover.c > @@ -703,16 +703,22 @@ static int __init kho_parse_bootmem_size(char *p) > if (p[len - 1] == '%') { > /* unsigned int max is 4,294,967,295, 10 chars */ > char s_scale[11] = {}; > + unsigned int scale; > int ret = 0; > > if (len > ARRAY_SIZE(s_scale)) > return -EINVAL; > > memcpy(s_scale, p, len - 1); > - ret = kstrtouint(s_scale, 10, &bootmem_scale); > - if (!ret) > - pr_notice("bootmem scale is %d%%\n", bootmem_scale); > - return ret; > + ret = kstrtouint(s_scale, 10, &scale); > + if (ret) > + return ret; > + if (!scale) > + return -EINVAL; Reviewed-by: Mukesh Pilaniya > + > + bootmem_scale = scale; > + pr_notice("bootmem scale is %d%%\n", bootmem_scale); > + return 0; > } > > /* parse ll[KMG],mm[KMG],nn[KMG] */ > -- Regards, Mukesh Pilaniya