The hardcoded kWebPageChunkSize of 768 bytes caused the task watchdog
to trigger when serving the web panel over HTTPS. Each call to
httpd_resp_send_chunk() results in a separate TLS record encryption
via mbedTLS, which on ESP32-S3 uses DMA-backed AES-GCM (esp_aes_process_dma).
The gdma_disconnect() call inside that path enters a critical section,
blocking the IDLE0 task. With 768-byte chunks, a large page response
requires many such DMA operations in tight succession, starving the IDLE
task long enough to trip the watchdog.
Replacing the hardcoded value with MBEDTLS_SSL_OUT_CONTENT_LEN aligns the
chunk size to the TLS output record buffer, minimising the number of TLS
records (and thus DMA encryption operations) needed to send a full page,
and keeping the httpd task within the watchdog timeout.
Fixes: task_wdt abort in sendProgmemChunked() -> httpd_ssl_send() ->
esp_aes_process_dma() -> gdma_disconnect() on ESP32-S3.
Valentin V. Bartenev
4d404f5301