From: Alex Markuze <amarkuze@redhat.com>
Date: Tue, 18 Mar 2025 20:44:27 +0000 (+0000)
Subject: pf: debugging pf corruption
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=6b8dc07ddf5f9d11f342934846855b4071f7147c;p=ceph-client.git

pf: debugging pf corruption
---

diff --git a/net/ceph/ceph_san_logger.c b/net/ceph/ceph_san_logger.c
index 1862b22a9612..2cc29e1e7e1a 100644
--- a/net/ceph/ceph_san_logger.c
+++ b/net/ceph/ceph_san_logger.c
@@ -143,6 +143,7 @@ void ceph_san_log(const char *file, const char *func, unsigned int line, const c
     alloc = cephsan_pagefrag_alloc(&ctx->pf, needed_size);
     int loop_count = 0;
     while (!alloc) {
+        entry = cephsan_pagefrag_get_ptr_from_tail(&ctx->pf);
         if (loop_count++ >= 32) {
             pr_err("ceph_san_log: pagefrag stats - head: %u, tail: %u, size: %u, free: %d\n",
                   ctx->pf.head, ctx->pf.tail,
@@ -153,9 +154,16 @@ void ceph_san_log(const char *file, const char *func, unsigned int line, const c
 
             panic("ceph_san_log: failed to allocate entry after 8 retries");
         }
-        entry = cephsan_pagefrag_get_ptr_from_tail(&ctx->pf);
-        BUG_ON(entry->debug_poison != CEPH_SAN_LOG_ENTRY_POISON);
-        BUG_ON(entry->len == 0);
+        if (entry->debug_poison != CEPH_SAN_LOG_ENTRY_POISON || entry->len == 0) {
+            pr_err("ceph_san_log: pagefrag corruption detected\n");
+            pr_err("  head: %u, tail: %u, size: %u\n",
+                  ctx->pf.head, ctx->pf.tail, CEPHSAN_PAGEFRAG_SIZE);
+            pr_err("  active_elements: %u, alloc_count: %u\n",
+                  ctx->pf.active_elements, ctx->pf.alloc_count);
+            pr_err("  entry poison: %llx, len: %u\n",
+                  entry->debug_poison, entry->len);
+            BUG();
+        }
         cephsan_pagefrag_free(&ctx->pf, entry->len);
         alloc = cephsan_pagefrag_alloc(&ctx->pf, needed_size);
     }