From 37de782e3ef8c1fb635e6a5adc725e60a5443e39 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Fri, 26 Dec 2025 22:13:10 -1000
Subject: [PATCH] guard

---
 esphome/components/ota/ota_backend_esp8266.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/esphome/components/ota/ota_backend_esp8266.cpp b/esphome/components/ota/ota_backend_esp8266.cpp
index 38e9d214b26..fe829ab0629 100644
--- a/esphome/components/ota/ota_backend_esp8266.cpp
+++ b/esphome/components/ota/ota_backend_esp8266.cpp
@@ -96,6 +96,8 @@ OTAResponseTypes ESP8266OTABackend::begin(size_t image_size) {
   // NOLINTNEXTLINE(readability-static-accessed-through-instance)
   this->buffer_size_ = (ESP.getFreeHeap() > 2 * FLASH_SECTOR_SIZE) ? FLASH_SECTOR_SIZE : MIN_BUFFER_SIZE;
 
+  // ESP8266's umm_malloc guarantees 4-byte aligned allocations, which is required
+  // for spi_flash_write(). This is the same pattern used by Arduino's Updater class.
   this->buffer_ = make_unique<uint8_t[]>(this->buffer_size_);
   if (!this->buffer_) {
     return OTA_RESPONSE_ERROR_UNKNOWN;