mirror of https://github.com/acidanthera/audk.git
9fc1b85fd1
The patch fixes the bug that the memory under 1MB is modified by firmware in S3 boot. Root cause is a racing condition in MpInitLib: 1. BSP: WakeUpByInitSipiSipi is set by NotifyOnS3SmmInitDonePpi() 2. BSP: WakeUpAP() wakes all APs to run certain procedure. 2.1. AllocateResetVector() uses <1MB memory for wake up vector. 2.1. FillExchangeInfoData() resets NumApsExecuting to 0. 2.2. WaitApWakeup() waits AP to clear WAKEUP_AP_SIGNAL. 3. AP: ApWakeupFunction() clears WAKEUP_AP_SIGNAL to inform BSP. 5. BSP: FreeResetVector() restores the <1MB memory 4. AP: ApWakeupFunction() calls the certain procedure. 4.1. NumApsExecuting is decreased. #4.1 happens after the 1MB memory is restored so the result is memory below 1MB is changed by #4.1 It happens only when the AP executes procedure a bit longer. AP returns back to ApWakeupFunction() from procedure after BSP restores the <1MB memory. Since NumApsExecuting is only used when InitFlag == ApInitConfig for counting the processor count. The patch moves the NumApsExecuting decrease to the path when InitFlag == ApInitConfig. Signed-off-by: Ray Ni <ray.ni@intel.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Eric Dong <eric.dong@intel.com> Cc: Nandagopal Sathyanarayanan <nandagopal.sathyanarayanan@intel.com> |
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| .. | ||
| Ia32 | ||
| X64 | ||
| DxeMpInitLib.inf | ||
| DxeMpInitLib.uni | ||
| DxeMpLib.c | ||
| Microcode.c | ||
| MpLib.c | ||
| MpLib.h | ||
| PeiMpInitLib.inf | ||
| PeiMpInitLib.uni | ||
| PeiMpLib.c | ||