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To: rppt@kernel.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20230129090034.12310-1-zhangpeng.00@bytedance.com> <20230129090034.12310-3-zhangpeng.00@bytedance.com> From: Peng Zhang In-Reply-To: <20230129090034.12310-3-zhangpeng.00@bytedance.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 903FD140002 X-Stat-Signature: b81rrf4nqa8x88f974dpm1adykd3hj8f X-HE-Tag: 1674983665-12673 X-HE-Meta: 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 0c/VvIwD Q9OvLP0a26bnWrxH08lKw8TmJQd//OoPqynYZKAya8RYwGzlnN4H1X3WHX761iVO/OQajnvzsZuYXTwa2mM6PzrBFe+GRXqHscV1ER/XS5ui5BeAciyFCAtier0+o3gw7JMQ8r4IZ/VITABafAF3uCeh/OKSc0gYOa4Ujlz1lDvTT+CjE6fjxnANhUchbUCYYrtVRpsILx5pek3BwLlmIGVqUZAH/EcZpVvrWo/MUIVEUj5WBvT3xglG+x+x2lIgcN9gmX0AZio2kvP7seLzBb/me3q6B97z4E/TzBcDiw8nFEROxg4+J5+MoVDZtFLcg2DuFl8s1P7gyMgkZqD9V/J+UOI4fDW1TcaO/9q3Q16kxw+9FHhiolOruiEoklxZTqgwLn73tB8vT1iFcwWCn5t5FanfWB4KEdBmErIPfVuTi1FD/khNfeLEuAnPoC6ZNQtznKcZkJJQr6PJpnMtUjEvsMEMUAr1Hjs9LCK/hrN84ci4= X-Bogosity: Ham, tests=bogofilter, spamicity=0.033386, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi, Mike > @@ -581,7 +586,7 @@ static int __init_memblock memblock_add_range(struct memblock_type *type, > bool insert = false; > phys_addr_t obase = base; > phys_addr_t end = base + memblock_cap_size(base, &size); > - int idx, nr_new; > + int idx, nr_new, start_rgn = -1, end_rgn; > struct memblock_region *rgn; > > if (!size) > @@ -635,10 +640,14 @@ static int __init_memblock memblock_add_range(struct memblock_type *type, > #endif > WARN_ON(flags != rgn->flags); > nr_new++; > - if (insert) > + if (insert) { > + if (start_rgn == -1) We can't initialize start_rgn with 0 and use if(!start_rgn). If start_rgn is equal to 0, it will be reassigned. It is possible that we will eventually need start_rgn to be equal to 0, and it may be reassigned to a larger value that does not meet expectations. Thanks. > + start_rgn = idx; > + end_rgn = idx + 1; > memblock_insert_region(type, idx++, base, > rbase - base, nid, > flags); > + } > } > /* area below @rend is dealt with, forget about it */ > base = min(rend, end); > @@ -647,9 +656,13 @@ static int __init_memblock memblock_add_range(struct memblock_type *type, > /* insert the remaining portion */ > if (base < end) { > nr_new++; > - if (insert) > + if (insert) { > + if (start_rgn == -1) > + start_rgn = idx; > + end_rgn = idx + 1; > memblock_insert_region(type, idx, base, end - base, > nid, flags); > + } > } > > if (!nr_new) > @@ -666,7 +679,7 @@ static int __init_memblock memblock_add_range(struct memblock_type *type, > insert = true; > goto repeat; > } else { > - memblock_merge_regions(type); > + memblock_merge_regions(type, start_rgn, end_rgn); > return 0; > } > } > @@ -902,7 +915,7 @@ static int __init_memblock memblock_setclr_flag(phys_addr_t base, > r->flags &= ~flag; > } > > - memblock_merge_regions(type); > + memblock_merge_regions(type, start_rgn, end_rgn); > return 0; > } > > @@ -1275,7 +1288,7 @@ int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size, > for (i = start_rgn; i < end_rgn; i++) > memblock_set_region_node(&type->regions[i], nid); > > - memblock_merge_regions(type); > + memblock_merge_regions(type, start_rgn, end_rgn); > #endif > return 0; > } Sincerely yours, Peng.