4.17-stable review patch. If anyone has any objections, please let me know.
------------------ From: Tom Lendacky <[email protected]> commit f426d2b20f1cd63818873593031593e15c3db20b upstream. The wait_event() function is used to detect command completion. The interrupt handler will set the wait condition variable when the interrupt is triggered. However, the variable used for wait_event() is initialized after the command has been submitted, which can create a race condition with the interrupt handler and result in the wait_event() never returning. Move the initialization of the wait condition variable to just before command submission. Fixes: 200664d5237f ("crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support") Cc: <[email protected]> # 4.16.x- Signed-off-by: Tom Lendacky <[email protected]> Reviewed-by: Brijesh Singh <[email protected]> Acked-by: Gary R Hook <[email protected]> Acked-by: Gary R Hook <[email protected]> Signed-off-by: Herbert Xu <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/crypto/ccp/psp-dev.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/crypto/ccp/psp-dev.c +++ b/drivers/crypto/ccp/psp-dev.c @@ -78,8 +78,6 @@ done: static void sev_wait_cmd_ioc(struct psp_device *psp, unsigned int *reg) { - psp->sev_int_rcvd = 0; - wait_event(psp->sev_int_queue, psp->sev_int_rcvd); *reg = ioread32(psp->io_regs + PSP_CMDRESP); } @@ -140,6 +138,8 @@ static int __sev_do_cmd_locked(int cmd, iowrite32(phys_lsb, psp->io_regs + PSP_CMDBUFF_ADDR_LO); iowrite32(phys_msb, psp->io_regs + PSP_CMDBUFF_ADDR_HI); + psp->sev_int_rcvd = 0; + reg = cmd; reg <<= PSP_CMDRESP_CMD_SHIFT; reg |= PSP_CMDRESP_IOC;
