Two "echo 0 > /sys/kernel/kexec_crash_size" OOPSes kernel. Also content of this file is invalid after first shrink to zero: it shows 1 instead of 0. This scenario is unlikely to happen often (root privs, valid crashkernel= in cmdline, dump-capture kernel not loaded), I hit it only by chance. This patch fixes it.
Unified · Split
| @@ -1134,11 +1134,9 @@ int crash_shrink_memory(unsigned long new_size) · 1133 unmodified lines | |||
| 1134 | 1134 | ||
| 1135 | free_reserved_phys_range(end, crashk_res.end); | 1135 | free_reserved_phys_range(end, crashk_res.end); |
| 1136 | 1136 | ||
| 1137 | if (start == end) { | 1137 | if (start == end) |
| 1138 | crashk_res.end = end; | ||
| 1139 | release_resource(&crashk_res); | 1138 | release_resource(&crashk_res); |
| 1140 | } else | 1139 | crashk_res.end = end - 1; |
| 1141 | crashk_res.end = end - 1; | ||
| 1142 | 1140 | ||
| 1143 | unlock: | 1141 | unlock: |
| 1144 | mutex_unlock(&kexec_mutex); | 1142 | mutex_unlock(&kexec_mutex); |