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94ce3b64c6
Currently, tls_device_down synchronizes with tls_device_resync_rx using RCU, however, the pointer to netdev is stored using WRITE_ONCE and loaded using READ_ONCE. Although such approach is technically correct (rcu_dereference is essentially a READ_ONCE, and rcu_assign_pointer uses WRITE_ONCE to store NULL), using special RCU helpers for pointers is more valid, as it includes additional checks and might change the implementation transparently to the callers. Mark the netdev pointer as __rcu and use the correct RCU helpers to access it. For non-concurrent access pass the right conditions that guarantee safe access (locks taken, refcount value). Also use the correct helper in mlx5e, where even READ_ONCE was missing. The transition to RCU exposes existing issues, fixed by this commit: 1. bond_tls_device_xmit could read netdev twice, and it could become NULL the second time, after the NULL check passed. 2. Drivers shouldn't stop processing the last packet if tls_device_down just set netdev to NULL, before tls_dev_del was called. This prevents a possible packet drop when transitioning to the fallback software mode. Fixes: |
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| acpi | ||
| asm-generic | ||
| clocksource | ||
| crypto | ||
| drm | ||
| dt-bindings | ||
| keys | ||
| kunit | ||
| kvm | ||
| linux | ||
| math-emu | ||
| media | ||
| memory | ||
| misc | ||
| net | ||
| pcmcia | ||
| ras | ||
| rdma | ||
| scsi | ||
| soc | ||
| sound | ||
| target | ||
| trace | ||
| uapi | ||
| ufs | ||
| vdso | ||
| video | ||
| xen | ||