kho: fix missing early_memunmap() call in kho_populate()

Patch series "two fixes in kho_populate()", v3.


This patch (of 2):

kho_populate() returns without calling early_memunmap() on success path,
this will cause early ioremap virtual address space leak.

Link: https://lkml.kernel.org/r/20260212111146.210086-1-ranxiaokai627@163.com
Link: https://lkml.kernel.org/r/20260212111146.210086-2-ranxiaokai627@163.com
Fixes: b50634c ("kho: cleanup error handling in kho_populate()")
Signed-off-by: Ran Xiaokai <ran.xiaokai@zte.com.cn>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Author: ranxiaokai

kernel/liveupdate/kexec_handover.c

@@ -1463,36 +1463,37 @@ void __init kho_populate(phys_addr_t fdt_phys, u64 fdt_len,
 	struct kho_scratch *scratch = NULL;
 	phys_addr_t mem_map_phys;
 	void *fdt = NULL;
+	bool populated = false;
 	int err;
 
 	/* Validate the input FDT */
 	fdt = early_memremap(fdt_phys, fdt_len);
 	if (!fdt) {
 		pr_warn("setup: failed to memremap FDT (0x%llx)\n", fdt_phys);
-		goto err_report;
+		goto report;
 	}
 	err = fdt_check_header(fdt);
 	if (err) {
 		pr_warn("setup: handover FDT (0x%llx) is invalid: %d\n",
 			fdt_phys, err);
-		goto err_unmap_fdt;
+		goto unmap_fdt;
 	}
 	err = fdt_node_check_compatible(fdt, 0, KHO_FDT_COMPATIBLE);
 	if (err) {
 		pr_warn("setup: handover FDT (0x%llx) is incompatible with '%s': %d\n",
 			fdt_phys, KHO_FDT_COMPATIBLE, err);
-		goto err_unmap_fdt;
+		goto unmap_fdt;
 	}
 
 	mem_map_phys = kho_get_mem_map_phys(fdt);
 	if (!mem_map_phys)
-		goto err_unmap_fdt;
+		goto unmap_fdt;
 
 	scratch = early_memremap(scratch_phys, scratch_len);
 	if (!scratch) {
 		pr_warn("setup: failed to memremap scratch (phys=0x%llx, len=%lld)\n",
 			scratch_phys, scratch_len);
-		goto err_unmap_fdt;
+		goto unmap_fdt;
 	}
 
 	/*
@@ -1509,7 +1510,7 @@ void __init kho_populate(phys_addr_t fdt_phys, u64 fdt_len,
 		if (WARN_ON(err)) {
 			pr_warn("failed to mark the scratch region 0x%pa+0x%pa: %pe",
 				&area->addr, &size, ERR_PTR(err));
-			goto err_unmap_scratch;
+			goto unmap_scratch;
 		}
 		pr_debug("Marked 0x%pa+0x%pa as scratch", &area->addr, &size);
 	}
@@ -1529,16 +1530,17 @@ void __init kho_populate(phys_addr_t fdt_phys, u64 fdt_len,
 	kho_in.scratch_phys = scratch_phys;
 	kho_in.mem_map_phys = mem_map_phys;
 	kho_scratch_cnt = scratch_cnt;
-	pr_info("found kexec handover data.\n");
 
-	return;
+	populated = true;
+	pr_info("found kexec handover data.\n");
 
-err_unmap_scratch:
+unmap_scratch:
 	early_memunmap(scratch, scratch_len);
-err_unmap_fdt:
+unmap_fdt:
 	early_memunmap(fdt, fdt_len);
-err_report:
-	pr_warn("disabling KHO revival\n");
+report:
+	if (!populated)
+		pr_warn("disabling KHO revival\n");
 }
 
 /* Helper functions for kexec_file_load */