diff options
Diffstat (limited to 'pkg/sentry/kernel/task.go')
| -rw-r--r-- | pkg/sentry/kernel/task.go | 43 |
1 files changed, 34 insertions, 9 deletions
diff --git a/pkg/sentry/kernel/task.go b/pkg/sentry/kernel/task.go index ab0c6c4aa..d25a7903b 100644 --- a/pkg/sentry/kernel/task.go +++ b/pkg/sentry/kernel/task.go @@ -489,18 +489,43 @@ type Task struct { // netns is protected by mu. netns is owned by the task goroutine. netns bool - // If rseqPreempted is true, before the next call to p.Switch(), interrupt - // RSEQ critical regions as defined by tg.rseq and write the task - // goroutine's CPU number to rseqCPUAddr. rseqCPU is the last CPU number - // written to rseqCPUAddr. + // If rseqPreempted is true, before the next call to p.Switch(), + // interrupt rseq critical regions as defined by rseqAddr and + // tg.oldRSeqCritical and write the task goroutine's CPU number to + // rseqAddr/oldRSeqCPUAddr. // - // If rseqCPUAddr is 0, rseqCPU is -1. + // We support two ABIs for restartable sequences: // - // rseqCPUAddr, rseqCPU, and rseqPreempted are exclusive to the task - // goroutine. + // 1. The upstream interface added in v4.18, + // 2. An "old" interface never merged upstream. In the implementation, + // this is referred to as "old rseq". + // + // rseqPreempted is exclusive to the task goroutine. rseqPreempted bool `state:"nosave"` - rseqCPUAddr usermem.Addr - rseqCPU int32 + + // rseqCPU is the last CPU number written to rseqAddr/oldRSeqCPUAddr. + // + // If rseq is unused, rseqCPU is -1 for convenient use in + // platform.Context.Switch. + // + // rseqCPU is exclusive to the task goroutine. + rseqCPU int32 + + // oldRSeqCPUAddr is a pointer to the userspace old rseq CPU variable. + // + // oldRSeqCPUAddr is exclusive to the task goroutine. + oldRSeqCPUAddr usermem.Addr + + // rseqAddr is a pointer to the userspace linux.RSeq structure. + // + // rseqAddr is exclusive to the task goroutine. + rseqAddr usermem.Addr + + // rseqSignature is the signature that the rseq abort IP must be signed + // with. + // + // rseqSignature is exclusive to the task goroutine. + rseqSignature uint32 // copyScratchBuffer is a buffer available to CopyIn/CopyOut // implementations that require an intermediate buffer to copy data |